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. Example: Fred kept a tank of guppies by the windowsill.
By extension, any tiny fish.
A tube holding paintballs before they are loaded into the gun. Example: 2001, John R. Little, Curtis Wong, Ultimate Paintball Field Guide (page 177)
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