1. (adj)indefinite vague or not clearly defined or stated Antonyms: certain(a), decided, decisive, distinct, certain(p), definite
2. (adj)indefinite not decided or not known Antonyms: certain(p), certain(a), decisive, decided, definite, distinct
Synonyms, Thesaurus & Antonyms of 'indefinite'
English Synonyms and Antonyms
1. indefinite Equivocal (L. equus, equal, and vox, voice, word) denotes that which may equally well be understood in either of two or more ways. Ambiguous (L. ambi, around, and ago, drive, lead) signif Synonyms: equivocal, ambiguous, enigmatical, indistinct, questionable, doubtful, indefinite, obscure, suspicious, dubious, indeterminate, perplexing, uncertain, enigmatic Antonyms: certain, evident, lucid, perspicuous, unequivocal, clear, indisputable, manifest, plain, unquestionable, distinct, indubitable, obvious, unambiguous, unquestioned
Synonyms for indefinite 
