What are the best answers for “a sign of something about to happen”?

omen, portent, presage, prognostic.

How many letters does the top answer for “a sign of something about to happen” have?

The most common answer is omen (4 letters).

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

omen 4 letters wn-def

a sign of something about to happen

portent 7 letters wn-def

a sign of something about to happen

presage 7 letters wn-def

indicate, as with a sign or an omen

prognostic 10 letters wn-def

a sign of something about to happen

a rate at which something happens 50% similar → swiftness