From brim + -er.
brimmer (plural brimmers)
- A cup brimming over with liquid.
- 1851, Herman Melville, Moby-Dick:
- No wonder, then, that they made a straight wake for the whale's mouth--the bar--when the wrinkled little old Jonah, there officiating, soon poured them out brimmers all round.
- (dialect) A hat with a brim, especially a straw hat.