How many letters does the top answer for “breathe spasmodically, and make a sound” have?

The most common answer is hiccough (8 letters).

Crossword clue: breathe spasmodically, and make a sound

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

hiccough 8 letters wn-def

the state of having reflex spasms of the diaphragm accompanied by a rapid closure of the glottis producing an audible so

hiccup 6 letters wn-def

the state of having reflex spasms of the diaphragm accompanied by a rapid closure of the glottis producing an audible so