How many letters does the top answer for “an approach to psychology that emphasizes observable measurable behavior” have?

The most common answer is behaviorism (11 letters).

Crossword clue: an approach to psychology that emphasizes observable measurable behavior

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

behaviorism 11 letters wn-def

an approach to psychology that emphasizes observable measurable behavior

behaviourism 12 letters wn-def

an approach to psychology that emphasizes observable measurable behavior