indefinite
in-def-i-nite
adjective
In grammar, referring to something not specific or previously identified.
"'A' and 'an' are indefinite articles."
adjective
Not clearly defined, precise, or limited; often vague or uncertain.
"The project has an indefinite completion date."
Thesaurus
Synonyms: noncommittal, nebulous, coy, unfixed, indecisive, one, uncertain
Antonyms: definite