How many letters does the top answer for “markedly different from an accepted norm” have?

The most common answer is aberrant (8 letters).

Crossword clue: markedly different from an accepted norm

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

aberrant 8 letters wn-def

one whose behavior departs substantially from the norm of a group

deviant 7 letters wn-def

a person whose behavior deviates from what is acceptable especially in sexual behavior

deviate 7 letters wn-def

turn aside; turn away from

a state or condition markedly different from the norm 50% similar → aberrance, aberrancy, aberration