guppy
Concise Oxford English Dictionary © 2008 Oxford University Press:
guppy /ˈgʌpi/
▶noun (pl. guppies) a small live-bearing freshwater fish, native to tropical America and widely kept in aquaria. [Poecilia reticulata.]
– origin 1920s: named after the Trinidadian clergyman R. J. Lechmere Guppy, who sent the first specimen to the British Museum.
'guppy' also found in these Oxford entries:

