Butter boat

a small vessel for holding melted butter at table.

See also: Butter

References in classic literature ?
Very clever were some of their productions, pasteboard guitars, antique lamps made of old-fashioned butter boats covered with silver paper, gorgeous robes of old cotton, glittering with tin spangles from a pickle factory, and armor covered with the same useful diamond shaped bits left inn sheets when the lids of preserve pots were cut out.
Nut butter Boat Load a few celery sticks with almond, cashew or walnut butter and raisins.
Then there were the butter boats and the potato boats.