How many letters does the top answer for “having a valence of five” have?

The most common answer is pentavalent (11 letters).

Crossword clue: having a valence of five

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

pentavalent 11 letters wn-def

having a valence of five

having a valence of 1 67% similar → monovalent

having a valence of three 50% similar → trivalent

having a valence of two or having two valences 50% similar → divalent