A salmon that has returned to fresh water after a single winter at sea.
- ‘The first grilse of the season was also caught during this period.’
- ‘A good amount of rain is forecast for the coming days which should bring the grilse in from the bay.’
- ‘Four grilse were caught at Durkanís Pool, one of 5 lb by a German angler and the rest higher up the river.’
- ‘The sort of rod that you'd use for sea trout or grilse should suffice.’
- ‘The grilse are still here in very good numbers, and the fishing prospects for the week ahead are excellent.’
Late Middle English: of unknown origin.