How many letters does the top answer for “the quality or attribute of being firm and steadfast” have?

The most common answer is stability (9 letters).

Crossword clue: the quality or attribute of being firm and steadfast

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

stability 9 letters wn-def

the quality or attribute of being firm and steadfast

stableness 10 letters wn-def

the quality or attribute of being firm and steadfast

the state or quality of being firm. 50% similar → firmness