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steelhead vs. trout

steelhead
[steel-hed] / ˈstilˌhɛd /

noun

steelheads, plural steelhead plural

  1. a silvery rainbow trout that migrates to the sea before returning to fresh water to spawn.

trout
[trout] / traʊt /

noun

trout, plural trouts plural

  1. any of several game fishes of the genus Salmo, related to the salmon.

  2. any of various game fishes of the salmon family of the genus Salvelinus.

  3. any of several unrelated fishes, as a bass, Micropterus salmoides, a drum of the genus Cynoscion, or a greenling of the genus Hexagrammos.