How many letters does the top answer for “characterized by nervousness and quickness to take fright” have?

The most common answer is restiveness (11 letters).

Crossword clue: characterized by nervousness and quickness to take fright

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

restiveness 11 letters wn-def

characterized by nervousness and quickness to take fright

skittishness 12 letters wn-def

characterized by nervousness and quickness to take fright