How many letters does the top answer for “not conforming to or in accord with tradition” have?

The most common answer is nontraditional (14 letters).

Crossword clue: not conforming to or in accord with tradition

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

nontraditional 14 letters wn-def

not conforming to or in accord with tradition

untraditional 13 letters wn-def

not conforming to or in accord with tradition