Trout's appendage (3)
I believe the answer is:
fin
(Other definitions for fin that I've seen before include "Aerodynamic surface" , "Paddle-like organ" , "Swimmer" , "Part of an aircraft's tail" , "Thin projection for fish to steer itself" .)
I believe the answer is:
fin
(Other definitions for fin that I've seen before include "Aerodynamic surface" , "Paddle-like organ" , "Swimmer" , "Part of an aircraft's tail" , "Thin projection for fish to steer itself" .)