How many letters does the top answer for “the branch of science dealing with physical and biological aspects of the oceans” have?

The most common answer is oceanography (12 letters).

Crossword clue: the branch of science dealing with physical and biological aspects of the oceans

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

oceanography 12 letters wn-def

the branch of science dealing with physical and biological aspects of the oceans

oceanology 10 letters wn-def

the branch of science dealing with physical and biological aspects of the oceans