Reproduction by multiple individuals of different origin; or sexual reproduction in general as opposed to asexual reproduction.
From Greek keno- (relating to common or new) combined with -gamy (marriage, reproduction). Used in biology to describe organisms reproducing through mating rather than division.
Cenogamy is what most animals do—they need a partner to make babies—which is why it seems simple, but the word exists because biologists needed to distinguish it from weird organisms that can clone themselves.
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