How many letters does the top answer for “cast off hair, skin, horn, or feathers” have?

The most common answer is exuviate (8 letters).

Crossword clue: cast off hair, skin, horn, or feathers

4 answers found in Letterora's clue database (Wikidata facts, Open Trivia DB, WordNet and Webster definitions — all licensed sources).

exuviate 8 letters wn-def

cast off hair, skin, horn, or feathers

molt 4 letters wn-def

periodic shedding of the cuticle in arthropods or the outer skin in reptiles

moult 5 letters wn-def

periodic shedding of the cuticle in arthropods or the outer skin in reptiles

slough 6 letters wn-def

any outer covering that can be shed or cast off (such as the cast-off skin of a snake)