How many letters does the top answer for “pit viper with horny segments at the end of the tail that rattle when shaken” have?

The most common answer is rattler (7 letters).

Crossword clue: pit viper with horny segments at the end of the tail that rattle when shaken

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

rattler 7 letters wn-def

pit viper with horny segments at the end of the tail that rattle when shaken

rattlesnake 11 letters wn-def

pit viper with horny segments at the end of the tail that rattle when shaken