n. pl. trout or troutsIdiom:
1. Any of various salmonid food and game fishes of the genera Oncorhynchus, Salmo, and Salvelinus, having a streamlined, speckled body and usually inhabiting freshwater streams or lakes. These genera also include the salmons and the chars.
2. Any of various similar but unrelated fishes, such as the trout-perch.
old trout Chiefly British Offensive Slang
An elderly woman.
[Middle English troute, from Old English trūht, from Late Latin trūcta, perhaps from Greek trōktēs, a kind of sea fish with sharp teeth, from trōgein, to gnaw; see terə-1 in the Appendix of Indo-European roots.]
(click for a larger image)trout
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