How many letters does the top answer for “move along very quickly” have?

The most common answer is whizz (5 letters).

Crossword clue: move along very quickly

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

whizz 5 letters wn-def

someone who is dazzlingly skilled in any field

zoom 4 letters wn-def

move along very quickly

run or move very quickly or hastily 50% similar → dash, scoot, scud