How many letters does the top answer for “with a loud crash” have?

The most common answer is smash (5 letters).

Crossword clue: with a loud crash

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

smash 5 letters wn-def

hit hard

smashingly 10 letters wn-def

with a loud crash