Sexual partner

A sexual partner is a person with whom one engages in sex acts. Note that it is possible to have a sexual partner without having an intimate relationship or even an acquaintanceship with that person; viz., casual sex or sex with a prostitute.

A person may have one, none, or more than one sexual partners at any one time, and this pattern may change throughout life.

Terms related to sexual partners include:
 * virginity: the state prior to having a sexual partner; a small minority of people remain virgins throughout life
 * monogamy: having a single long-term sexual partner
 * marriage: a socially binding commitment to a partner
 * sexual infidelity: having a sexual relationship outside of a relationship that includes a commitment to have no other sexual partners
 * sexual fidelity: not having other sexual partners other than one's committed partner, even temporarily
 * serial monogamy: having a series of monogamous relationships, one after the other
 * polygamy: having multiple long-term sexual partners
 * polyandry: having multiple long-term male sexual partners
 * polygyny: having multiple long-term female sexual partners
 * polyamory: encompasses a wide range of relationships, including those above: polyamorous relationships may include both committed and casual relationships
 * sexual promiscuity: having casual sexual partners at will (compare with chastity)

Variations between cultures
Different cultures have different viewpoints and levels of tolerance for the various patterns of sexual activity.

The most common patterns in Western society are monogamy, serial monogamy and marriage. Polygamous marriage is typically not found in Western culture, except in specific minority religions, and is illegal in many places. However, sexual promiscuity is commonly accepted, and a minority have open relationships or practice polyamory.

Polyandry is banned in Islamic culture, and both polygyny and polyandry are found in some African cultures.