Mechanical Device With Blades That Drives a Boat

This page is the CodyCross answer for the clue below from Prehistory, Group 1251, Puzzle 5 (Settlements).

Question is: Mechanical Device With Blades That Drives a Boat

and the answer is: PROPELLER

Word Meaning:

PROPELLER — One who, or that which, propels.

Definitions from Wiktionary.