Final answer:
The terms used to describe the sexual union between a male and female are 'mating' for biological reproduction and 'marriage' for socially recognized unions, which can vary in form, including same-sex partnerships.
Step-by-step explanation:
The terms used to describe the sexual union between a male and female are mating and marriage. Mating refers to the biological union for the purpose of reproduction. It encompasses a wide variety of relationship structures across different species, from brief associations to lifelong pairings. On the other hand, marriage is the socially sanctioned union of two adults, which, in some societies, is traditionally between a male and a female for procreation and family life.
However, marriage patterns vary greatly, and many societies recognize same-sex unions as well. The United States, for instance, has legal same-sex marriage. It's important to understand that the term 'female' and 'male' in this context refer to the biological sex, which is defined by reproductive anatomy and genetic makeup, such as XX chromosomal structure for females and XY for males.