Syllable division derived from spelling — this word is not in the pronouncing dictionary, so no phonetic transcription is shown rather than a guessed one.
twenty-eight is a noun and adjective meaning "the cardinal number that is the sum of twenty-seven and one". It carries 2 recorded senses.
the cardinal number that is the sum of twenty-seven and one
Definitions, synonyms and semantic relations for twenty-eight come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. Full sources and licences.