How many letters does the top answer for “designed to deceive or mislead either deliberately or inadvertently” have?

The most common answer is deceptive (9 letters).

Crossword clue: designed to deceive or mislead either deliberately or inadvertently

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

deceptive 9 letters wn-def

designed to deceive or mislead either deliberately or inadvertently

misleading 10 letters wn-def

designed to deceive or mislead either deliberately or inadvertently