guppy

Etymology

From a name mistakenly assigned, Girardinus guppii, after biologist Robert J. L. Guppy, to previously assigned Poecilia reticulata.

noun

1. A 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.
   Fred kept a tank of guppies by the windowsill.
2. (by extension) Any tiny fish.
   Throw that one back; it’s just a guppy!
3. (paintball) A tube holding paintballs before they are loaded into the gun.
   I reached into my pack and grabbed a guppy to reload. Pouring in the contents, I kept my eyes ahead as I was supposed to do. 2001, John R. Little, Curtis Wong, Ultimate Paintball Field Guide, page 177
4. (climbing) A hold across the palm of the hand rather than the fingertips.