sillock
noun/ˈsɪ.lək/
Etymology From sill (“newly hatched young of fish, fry”) + -ock, ultimately from Old Norse síl, síld (“herring”), whence also dialectal Swedish sil (“the young of fish, fry”) and Norwegian sil (“sand-eel”). More at sile.
1
Scotland A pollock or a coalfish, sometimes especially a young coalfish.