boater

noun

1. Someone who travels by boat.
2. Synonym of boatman, particularly its captain.

   “In the summer of 1992, eight beaches were closed and swimmers were warned away because of colliform bacteria, caused by boaters emptying toilets directly into the lake or onto nearby shores. Park officials may soon supply the lake with floating waste disposal systems.”

3. A straw hat, very stiff, with a flat brim and crown.

   “Technically, Melania Trump was in attendance, but she chose to make herself almost invisible. Her dark boater hat was worn so low that it threw her entire face into shadow, and made eye contact with cameras or guests impossible.”