How many letters does the top answer for “a knob used to release the catch when opening a door” have?

The most common answer is doorhandle (10 letters).

Crossword clue: a knob used to release the catch when opening a door

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

doorhandle 10 letters wn-def

a knob used to release the catch when opening a door

doorknob 8 letters wn-def

a knob used to release the catch when opening a door