IPA: /ˈfɔːr.tɒp.mən/
KK: /ˈfɔːrˌtɑːp.mən/
A sailor who is assigned to work in the foretop, which is a platform high up on a ship's mast.
The foretopman climbed up the rigging to check the sails.
Foretopman → It is formed from "fore-" (meaning front or before) and "top" (from Old English *top*, meaning the highest point) and "man" (meaning a person). A foretopman is a sailor who works at the front of the ship, specifically in the highest part of the rigging.
Think of someone at the 'front' ('fore-') of the 'highest point' ('top') of a ship — that's why a foretopman is a sailor working up high at the front.
No commonly confused words.