Of or relating to the sex act or coitus(adjective)
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Use "coital" in a sentence
"But critics found possible reasons other than underlying biology for fertility drops: for example, sexual ennui — or, as they more technically put it, a diminution in coital frequency over the course of a marriage."
"Artificial insemination under controlled conditions would eliminate confounding factors such as variations in coital frequency or in sperm quality."
"Seeing as how that’s the same look your sister gets every time you’re engaged in coital “bliss”."