guppy

noun ! Definition from Wiktionary (CC BY-SA). Pronunciation from Wiktionary, via Kaikki.org. More about guppy at Wordnik → Where our words come from →

1. A species of tiny freshwater fish, Poecilia reticulata, popular in home aquariums, that usually has a plain body and black or dark blue tail for the females and a more colorful tail for the males. The guppies can vary in size, but males are 4 cm (1.6”) and females are 7 cm (2.8”).

   Fred kept a tank of guppies by the windowsill.

2. Any tiny fish.

   Throw that one back; it’s just a guppy!

3. A tube holding paintballs before they are loaded into the gun.