How many letters does the top answer for “another word for synonymousness” have?

The most common answer is synonymity (10 letters).

Crossword clue: another word for synonymousness

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

synonymity 10 letters gen-syn

the semantic relation that holds between two words that can (in a given context) express the same meaning

synonymy 8 letters gen-syn

the semantic relation that holds between two words that can (in a given context) express the same meaning

another word for about 50% similar → approximately, roughly, some

another word for terms 50% similar → footing

another word for under 50% similar → nether

another word for word 50% similar → phrase