Syllable division derived from spelling — this word is not in the pronouncing dictionary, so no phonetic transcription is shown rather than a guessed one.
four-hundredth is an adjective meaning "the ordinal number of four hundred in counting order". It carries one recorded sense.
Definitions, synonyms and semantic relations for four-hundredth come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. Full sources and licences.