halibut Meaning, Definition & Usage

  1. noun lean flesh of very large flatfish of Atlantic or Pacific
  2. noun marine food fish of the northern Atlantic or northern Pacific; the largest flatfish and one of the largest teleost fishes
    holibut.

WordNet

Hal"i*but noun
Etymology
OE. hali holy + but, butte, flounder; akin to D. bot, G. butte; cf. D. heilbot, G. heilbutt. So named as being eaten on holidays. See Holy, Holiday.
Definitions
  1. (Zoöl.) A large, northern, marine flatfish (Hippoglossus vulgaris), of the family Pleuronectidæ. It often grows very large, weighing more than three hundred pounds. It is an important food fish. Written also holibut.

Webster 1913