Definition of smolt in English:



  • A young salmon (or trout) after the parr stage, when it becomes silvery and migrates to the sea for the first time.

    • ‘During our 1996 investigations, we found evidence of predation on a salmon smolt by striped bass, and we utilized available ultrasonic tags to monitor the movements of striped bass.’
    • ‘Young fish were also reared in hatchery tanks and released as smolts, the stage at which salmon head to sea before traveling to northerly feeding grounds.’
    • ‘Perhaps only 50 reach the ocean as smolts - young salmon that have taken on the characteristic silvery color - about two years later.’
    • ‘While in freshwater, Chinook Salmon fry and smolts feed on plankton and then terrestrial and aquatic insects, amphipods and crustaceans.’
    • ‘One or two years later, the smolts begin to migrate to the Pacific, where they live for one to three years before returning to the river.’


Late Middle English (originally Scots and northern English): of unknown origin; compare with smelt.