A Dolphin's Fin
This page is the CodyCross answer for the clue below from Greece, Group 676, Puzzle 4 (Irene Papas).
Question
A Dolphin's Fin
Answer
FLIPPER
Word Meaning:
FLIPPER — In marine mammals such as whales (or other aquatic animals such as sea turtles), a wide, flat limb adapted for swimming.
Definitions from Wiktionary.