How many letters does the top answer for “the act of setting in operation” have?

The most common answer is startup (7 letters).

Crossword clue: the act of setting in operation

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

startup 7 letters wn-def

the act of setting in operation

the act or operation of cleansing. 50% similar → mundification

the act or operation of levigating. 50% similar → levigation

the act or operation of systematizing. 50% similar → systematization