'eared-seal' originates from Modern English, specifically the compound of 'eared' (from Old English 'ēared') and 'seal' (from Old English 'seolh'), where 'eared' originally meant 'having an ear' and 'seal' referred to the marine mammal.

'eared-seal' was formed as a descriptive compound in post-medieval English to distinguish members of the family Otariidae from 'earless' seals (phocids); 'eared' derives from Old English 'ēared' and 'seal' from Old English 'seolh', and the compound became established in zoological usage.

Initially it meant simply 'a seal that has a visible external ear'; over time the term came to be used specifically for members of the family Otariidae (sea lions and fur seals).