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Philandering from WikiPedia:

In human sexual behavior, promiscuity denotes sex with relatively many partners. In human cultures where polygamy is accepted, it is distinguished from promiscuity.

Promiscuity is common in many animal species. Some species have promiscuous mating systems, ranging from polyandry and polygyny to mating systems with no stable relationships where mating between two individuals is a one-time event. Many species form stable pair bonds but still mate with other individuals outside the pair. In biology, incidents of promiscuity in species that form pair bonds are usually called extra-pair copulations.

What sexual behavior is considered socially acceptable, and what behavior is "promiscuous", varies much among different cultures, and within a culture different standards are often applied to people of different gender and civil status.

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