The missionary position or man-on-top position is generally a sex position in which a woman lies on her back and a man lies on top of her while they face each other and engage in sexual intercourse or other sexual activity.

• In general, early modern Catholic doctrine held that sexual relations were acceptable as long as they were within marriage, not done on Sundays or other church holidays, done in a way which would allow procreation, and did not upset the proper sexual order, which meant the man had to be on top (what has since been termed the “missionary position”).
  • Merry E. Wiesner-Hanks, Early Modern Europe 1450–1789 (2nd ed, 2013), Ch. 2 : Individuals in society, 1450–1600

• One presumes that all of those jokes about the missionary position might have a kernel of truth.
  • Michael Ruse, Atheism: What Everyone Needs to Know (2015), Ch. 12 : The Meaningful Life

• Bonobos and humans enjoy many different copulatory positions, with ventral-ventral (missionary position) appearing to be preferred by bonobo females and rear-entry by males, while chimps prefer rear-entry almost exclusively.
  • Christopher Ryan and Cacilda Jethá, Sex at Dawn (2010)

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Missionary position