Syllable division derived from spelling — this word is not in the pronouncing dictionary, so no phonetic transcription is shown rather than a guessed one.
sixty-nine is a noun and adjective meaning "oral sex practiced simultaneously by two people". It carries 2 recorded senses.
oral sex practiced simultaneously by two people
Definitions, synonyms and semantic relations for sixty-nine come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. Full sources and licences.