How many letters does the top answer for “the condition or quality of being immobile; fixedness in place or state.” have?

The most common answer is immobility (10 letters).

Crossword clue: the condition or quality of being immobile; fixedness in place or state.

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

immobility 10 letters web-def

remaining in place

the state, conditions, or quality of being brassy. 50% similar → brassiness