How many letters does the top answer for “belonging to the same genus; allied in origin, nature, or action. r. owen.” have?

The most common answer is congeneric (10 letters).

Crossword clue: belonging to the same genus; allied in origin, nature, or action. r. owen.

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

congeneric 10 letters web-def

an animal or plant that bears a relationship to another (as related by common descent or by membership in the same genus

congenerical 12 letters web-def

Belonging to the same genus; allied in origin, nature, or action. R. Owen.