IPA: /ˈboʊtər/
KK: /ˈboʊtər/
A person who operates or rides in a boat, especially for leisure, or a type of hat made of stiff straw with a flat crown.
She wore a stylish boater while sailing on the lake.
Boater → The word is formed from "boat" (from Old English *bāt*, meaning a small vessel for traveling on water) and "-er" (meaning a person who). A boater is a person who operates or is associated with a boat.
Think of someone who is associated with a 'boat' — the '-er' just means a person. A boater is someone who operates or is involved with a boat.