How many letters does the top answer for “author of the trumpet of the swan” have?

The most common answer is white (5 letters).

Crossword clue: author of the trumpet of the swan

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

white 5 letters wd-fact-v3

being of the achromatic color of maximum lightness; having little or no hue owing to reflection of almost all incident l

author of swan lake 50% similar → petipa, tchaikovsky

author of the black swan 50% similar → taleb

wrote the trumpet of the swan 50% similar → white