How many letters does the top answer for “a follower of aristotle or an adherent of aristotelianism” have?

The most common answer is aristotelian (12 letters).

Crossword clue: a follower of aristotle or an adherent of aristotelianism

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

aristotelian 12 letters wn-def

of or relating to Aristotle or his philosophy

peripatetic 11 letters wn-def

a follower of Aristotle or an adherent of Aristotelianism