How many letters does the top answer for “the time at which something is supposed to begin” have?

The most common answer is outset (6 letters).

Crossword clue: the time at which something is supposed to begin

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

outset 6 letters wn-def

the time at which something is supposed to begin

showtime 8 letters wn-def

the time at which something is supposed to begin