plural noun
Poe·​ci·​li·​idae | \ ˌpēsəˈlīəˌdē\

Definition of Poeciliidae

: a large family of small New World viviparous fishes (order Microcyprini) comprising the topminnows and having the male anal fin modified as a copulatory organ — compare guppy, swordtail

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History and Etymology for Poeciliidae

New Latin, from Poecilia, type genus (from Greek poikilia condition of being marked with various colors, from poikil- poecil- + -ia -y) + -idae

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