How many letters does the top answer for “any of a class of organic compounds containing the cyano radical -cn” have?

The most common answer is nitril (6 letters).

Crossword clue: any of a class of organic compounds containing the cyano radical -cn

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

nitril 6 letters wn-def

any of a class of organic compounds containing the cyano radical -CN

nitrile 7 letters wn-def

any of a class of organic compounds containing the cyano radical -CN