40 Human sexuality

Eros is a concept in ancient Greek philosophy referring to sensual or passionate love, from which the term erotic is derived. Eros has also been used in philosophy and psychology in a much wider sense, almost as an equivalent to "life energy". Protestant author C.S. Lewis posits it as one of the four ancient Greek words for love in Christianity, alongside storge, philia, and agape.

Animal roleplay is a form of roleplay where at least one participant plays the part of a non-human animal. As with most forms of roleplay, its uses include play and psychodrama.

A bed is a piece of furniture which is used as a place to sleep, relax, or engage in sexual activities.

The breast is one of two prominences located on the upper ventral region of the torso of primates. In females, it serves as the mammary gland, which produces and secretes milk to feed infants. Both females and males develop breasts from the same embryological tissues. At puberty, estrogens, in conjunction with growth hormone, cause breast development in female humans and to a much lesser extent in other primates. Breast development in other primate females generally only occurs with pregnancy.

The buttocks are two rounded portions of the exterior anatomy of most mammals, located on the posterior of the pelvic region. In humans, the buttocks are located between the lower back and the perineum. They are composed of a layer of exterior skin and underlying subcutaneous fat superimposed on a left and right gluteus maximus and gluteus medius muscles. The two gluteus maximus muscles are the largest muscles in the human body. They are responsible for achieving the upright posture when the body is bent at the waist; maintaining the body in the upright posture by keeping the hip joints extended; and propelling the body forward via further leg (hip) extension when walking or running. In the seated position, the buttocks bear the weight of the upper body and take that weight off the feet.

The casting couch is a euphemism for the practice of soliciting sexual favors from a job applicant in exchange for employment in the entertainment industry, primarily acting roles. The practice is illegal in the United States. Predominantly male casting directors and film producers use the casting couch to extract sex from aspiring actors in Hollywood, Bollywood, Broadway, and other segments of the industry. The term casting couch originally referred to physical couches in the casting office, but is now a metonym for the phenomenon as a whole. Depictions of casting couch sexual encounters have also become a genre of pornography.

Catfight is a term for an altercation between two females, often characterized as involving scratching, slapping, punching, biting, hair-pulling, and shirt-shredding. It can also be used to describe women insulting each other verbally or engaged in an intense competition for men, power, or occupational success. The catfight has been a staple of American news media and popular culture since the 1940s, and use of the term is often considered derogatory or belittling. Some observers argue that in its purest form, the word refers to two women, one blonde and the other a brunette, fighting each other. However, the term is not exclusively used to indicate a fight between women, and many formal definitions do not invoke gender.

In many traditions and statutes of civil or religious law, the consummation of a marriage, often called simply consummation, is the first act of sexual intercourse between two people, either following their marriage to each other or after a short or prolonged romantic/sexual attraction. The definition of consummation usually refers to penile-vaginal sexual penetration, but some religious doctrines hold that there is an additional requirement that there must not be any contraception used.

A sex strike, sometimes called a sex boycott, is a strike, a method of non-violent resistance in which one or multiple persons refrain from sex with their partners to achieve certain goals. It is a form of temporary sexual abstinence.

Cruising for sex, or cruising, is walking or driving about a locality, called a cruising ground, in search of a sex partner, usually of the anonymous, casual, one-time variety. The term is also used when technology is used to find casual sex, such as using an Internet site or a telephone service.

Human sexual promiscuity is the practice of having many different sexual partners. In the case of men, this behavior of sexual nondiscrimination and hypersexuality is referred to as satyriasis, while in the case of women, this behavior is conventionally known as nymphomania. Both conditions are regarded as possibly compulsive and pathological qualities, closely related to hyper-sexuality. The results of, or costs associated with, these behaviors are the effects of human sexual promiscuity.

An erogenous zone is an area of the human body that has heightened sensitivity, the stimulation of which may generate a sexual response, such as relaxation, sexual fantasies, sexual arousal and orgasm.

Eroticism is a quality that causes sexual feelings, as well as a philosophical contemplation concerning the aesthetics of sexual desire, sensuality, and romantic love. That quality may be found in any form of artwork, including painting, sculpture, photography, drama, film, music, or literature. It may also be found in advertising. The term may also refer to a state of sexual arousal or anticipation of such – an insistent sexual impulse, desire, or pattern of thoughts.

Extended female sexuality is where the female of a species mates despite being infertile. In most species, the female only engages in copulation when she is fertile. However, extended sexuality has been documented in old world primates, pair bonded birds and some insects. Extended sexuality is most prominent in human females who exhibit no change in copulation rate across the ovarian cycle.

Female hysteria was once a common medical diagnosis for women, which was described as exhibiting a wide array of symptoms, including anxiety, shortness of breath, fainting, nervousness, sexual desire, insomnia, fluid retention, heaviness in the abdomen, irritability, loss of appetite for food or sex, (paradoxically) sexually forward behaviour, and a "tendency to cause trouble for others". It is no longer recognized by medical authorities as a medical disorder. Its diagnosis and treatment were routine for hundreds of years in Western Europe.

Food and sexuality have been associated in various ways throughout history. Foods such as chocolate and oysters are said to be aphrodisiacs. In some cultures animal testicles and other items are consumed to increase sexual potency. Food items also provide symbolism, such as the biblical "forbidden fruit" or the cherry with its associations related to virginity. Food items are also used metaphorically in slang sexual terminology and poetry. Some foods are considered sensual for their appearance, texture and taste. Whipped cream, melted chocolate, jam, strawberries that are often dipped in chocolate and peanut butter are sometimes used for intimate titillation in an act known as sploshing. The relationship between food and sex has also been explored in books and cinema.

The term groupie is a slang word that refers to a fan of a particular musical group who follows this band around while they are on tour or who attends as many of their public appearances as possible, usually in hopes of getting to meet them. The term is often used in a gendered fashion, to describe young women who follow these individuals in hopes of establishing a sexual relationship with them or offering sex. The term is used to describe fans of music and sports, and admirers of public figures in other high-profile professions. It may have a pejorative connotation, as some groupies may be sexually promiscuous.

Human mate guarding refers to behaviours employed by both males and females with the aim of maintaining reproductive opportunities and sexual access to a mate. It involves discouraging the current mate from abandoning the relationship whilst also warding off intrasexual rivals. It has been observed in many non-human animals, as well as humans. Sexual jealousy is one of the main causes of mate guarding behaviour. Both males and females use different strategies to retain a mate and there is evidence that suggests resistance to mate guarding also exists.

The mechanics of human sexuality or mechanics of sex, or more formally the biomechanics of human sexuality, is the study of the mechanics related to human sexual activity. Examples of topics include the biomechanical study of the strength of vaginal tissues and the biomechanics of male erectile function. The mechanics of sex under limit circumstances, such as sexual activity at zero-gravity in outer space, are also being studied.

The nipple is a raised region of tissue on the surface of the breast from which, in females, milk leaves the breast through the lactiferous ducts to feed an infant. The milk can flow through the nipple passively or it can be ejected by smooth muscle contractions that occur along the ductal system. The nipple is surrounded by the areola, which is often a darker color than the surrounding skin. A nipple is often called a teat when referring to non-humans. Nipple or teat can also be used to describe the flexible mouthpiece of a baby bottle. In humans, nipples of both males and females can be stimulated as part of sexual arousal. In many cultures, human female nipples are sexualized, or "regarded as sex objects and evaluated in terms of their physical characteristics and sexiness."

Physical attractiveness is the degree to which a person's physical features are considered aesthetically pleasing or beautiful. The term often implies sexual attractiveness or desirability, but can also be distinct from either. There are many factors which influence one person's attraction to another, with physical aspects being one of them. Physical attraction itself includes universal perceptions common to all human cultures such as facial symmetry, sociocultural dependent attributes and personal preferences unique to a particular individual.

Physical intimacy is sensual proximity or touching. It is an act or reaction, such as an expression of feelings, between people. Examples of physical intimacy include being inside someone's personal space, holding hands, hugging, kissing, caressing and sexual activity. Physical intimacy can often convey the real meaning or intention of an interaction in a way that accompanying speech simply cannot do. Physical intimacy can be exchanged between any people but as it is often used to communicate positive and intimate feelings, it most often occurs in people who have a preexisting relationship, whether familial platonic or romantic, with romantic relationships having increased physical intimacy. Several forms of romantic touch have been noted including holding hands, hugging, kissing, cuddling, caressing and massaging, and physical affection is highly correlated with overall relationship and partner satisfaction.

Prostitution is the business or practice of engaging in sexual activity in exchange for payment. Prostitution is sometimes described as sexual services, commercial sex or, colloquially, hooking. It is sometimes referred to euphemistically as "the world's oldest profession" in the English-speaking world. A person who works in this field is called a prostitute and is a type of sex worker.

Romance is an emotional feeling of love for, or a strong attraction towards another person, and the courtship behaviors undertaken by an individual to express those overall feelings and resultant emotions.

Sex in space, specifically human sexual activity in the weightlessness of outer space, presents difficulties due to Newton's third law. According to the law, if the couple remain attached, their movements will counter each other. Consequently, their actions will not change their velocity unless they are affected by another, unattached, object. Some difficulty could occur due to drifting into other objects. If the couple have a combined velocity relative to other objects, collisions could occur. There have been suggestions that conception and pregnancy in off-Earth environments could be an issue.

A sex scandal is a scandal involving allegations or information about possibly-immoral sexual activities being made public. Sex scandals are often associated with the sexual affairs of film stars, politicians, famous athletes or others in the public eye. Sex scandals receive attention if a prominent figure is involved, if there is a perception of hypocrisy, if a public figure's sexuality is non-normative, or if it involves non-consensual acts. A scandal may be based on reality, the product of false allegations, or a mixture of both. Whether the scandal is based in fact or not, it may lead to the celebrity disappearing from the public eye or to the resignation of prominent political figures.

Sex steroids, also known as gonadocorticoids and gonadal steroids, are steroid hormones that interact with vertebrate steroid hormone receptors. The sex steroids include the androgens, estrogens, and progestogens. Their effects are mediated by slow genomic mechanisms through nuclear receptors as well as by fast nongenomic mechanisms through membrane-associated receptors and signaling cascades. The term sex hormone is nearly always synonymous with sex steroid. The polypeptide hormones luteinizing hormone, follicle-stimulating hormone and gonadotropin-releasing hormone are usually not regarded as sex hormones, although they play major sex-related roles.

Sex work is "the exchange of sexual services, performances, or products for material compensation. It includes activities of direct physical contact between buyers and sellers as well as indirect sexual stimulation". Sex work only refers to voluntary sexual transactions; thus the term does not refer to human trafficking and other coerced or nonconsensual sexual transactions such as child prostitution. The transaction must take place between consenting adults who are of the legal age and mental capacity to consent and must take place without any methods of coercion. The term emphasizes the labor and economic implications of this type of work. Furthermore, some prefer the use of the term because it seemingly grants more agency to the sellers of these services.

Sexual abstinence or sexual restraint is the practice of refraining from some or all aspects of sexual activity for medical, psychological, legal, social, financial, philosophical, moral, or religious reasons. Asexuality is distinct from sexual abstinence; and celibacy is sexual abstinence generally motivated by factors such as an individual's personal or religious beliefs. Sexual abstinence before marriage is required in some societies by social norms, or, in some countries, even by laws, and is considered part of chastity.

Sexual guilt is a negative emotional response associated with the feeling of anxiety, guilt or shame in relation to sexual activity. It is also known as “sexual shame”.

Sexual objectification is the act of treating a person solely as an object of sexual desire. Objectification more broadly means treating a person as a commodity or an object without regard to their personality or dignity. Objectification is most commonly examined at the level of a society, but can also refer to the behavior of individuals and is a type of dehumanization.

Sexual selection in humans concerns the concept of sexual selection, introduced by Charles Darwin as an element of his theory of natural selection, as it affects humans. Sexual selection is a biological way one sex chooses a mate for the best reproductive success. Most compete with others of the same sex for the best mate to contribute their genome for future generations. This has shaped our evolution for many years, but reasons why humans choose their mates are hardly understood. Sexual selection is quite different in non-human animals than humans as they feel more of the evolutionary pressures to reproduce and can easily reject a mate. The role of sexual selection in human evolution has not been firmly established although neoteny has been cited as being caused by human sexual selection. It has been suggested that sexual selection played a part in the evolution of the anatomically modern human brain, i.e. the structures responsible for social intelligence underwent positive selection as a sexual ornamentation to be used in courtship rather than for survival itself, and that it has developed in ways outlined by Ronald Fisher in the Fisherian runaway model. Fisher also stated that the development of sexual selection was "more favourable" in humans.

Sexuality and disability is regarding the sexual behavior and practices of individuals with disabilities. Individuals with disabilities have a range of sexual desires and differ in the ways they choose to express their sexuality. Commonly, people with disabilities lack comprehensive sex education that would assist in their sexual lives. This roots from the idea that people with disabilities are asexual in nature and are not sexually active. Although some people with disabilities are asexual, it is a misconception to label all as such. Many people with disabilities lack rights and privileges that would enable them to have intimacy and relationships. When it comes to sexuality and disability there is a sexual discourse that surrounds it. The intersection of sexuality and disability is often associated with victimization, abuse, and purity.

A stripper or exotic dancer is a person whose occupation involves performing striptease in a public adult entertainment venue such as a strip club. At times, a stripper may be hired to perform at a bachelor party or other private event.

Tantric sex or sexual yoga refers to a wide range of practices carried on in Hinduist and Buddhist tantra to exercise sexuality in a ritualized or yogic context, often associated to antinomian or impure elements, like consumption of alcohol, and offerings of impure substances like meat to fierce deities. In particular, sexual fluids have been viewed as "power substances" and used ritualistically, either externally or internally.

Urethral intercourse or coitus per urethram is sexual penetration of the female urethra by an object such as a penis or a finger. It is not the same thing as urethral sounding, the act of inserting a specialized medical tool into the urethra as a form of sexual or fetishistic activity.

Urolagnia is a paraphilia in which sexual excitement is associated with the sight or thought of urine or urination.

A virginity auction is an auction, often publicized online, where a person seeks to sell their virginity. The winning bidder will win the right to be the first to have intercourse with the person.

Yoni, sometimes referred to as pindika, is an aniconic representation of the goddess Shakti in Hinduism. It is usually shown with linga – its masculine counterpart. Together, they symbolize the merging of microcosmos and macrocosmos, the divine eternal process of creation and regeneration, and the union of the feminine and the masculine that recreates all of existence. The yoni is conceptualized as nature's gateway of all births, particularly in the esoteric Kaula and Tantra practices, as well as the Shaktism and Shaivism traditions of Hinduism.