'Capelin' definitions:

Definition of 'capelin'

noun

Very small northern fish; forage for sea birds and marine mammals and other fishes [syn: capelin, capelan, caplin]

From: GCIDE

Capelin \Cape"lin\, n. [Cf. F. capelan, caplan.] (Zool.) Either of two small marine fishes formerly classified in the family Salmonid[ae], now within the smelt family Osmeridae: Mallotus villosus, very abundant on the coasts of Greenland, Iceland, Newfoundland, and Alaska; or {Mallotus catervarius}, found in the North Pacific. The Atlantic variety has been used as a bait for the cod. [Written also capelan and caplin.] [1913 Webster + PJC]
Note: This fish, which is like a smelt, is called by the Spaniards anchova, and by the Portuguese capelina. However the anchovy used as a food is a different fish. --Fisheries of U. S. (1884). [1913 Webster + PJC]