Crossword clue: having a sharp, lean, or thin back; as, a razor-backed hog, perch, etc.
1 answer found in Letterora's clue database (Wikidata facts, Open Trivia DB, WordNet and Webster definitions — all licensed sources).
Possible answers
any of several baleen whales of the family Balaenopteridae having longitudinal grooves on the throat and a small pointed