How many letters does the top answer for “author of the nonexistent knight” have?

The most common answer is calvino (7 letters).

Crossword clue: author of the nonexistent knight

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

calvino 7 letters wd-fact-v3

Italian writer of novels and short stories (born in Cuba) (1923-1987)

author of princess knight 50% similar → tezuka

author of the knights of the cross 50% similar → sienkiewicz

wrote the nonexistent knight 50% similar → calvino