indefinite

from The American Heritage® Dictionary of the English Language, 5th Edition.

• adjective Not definite, especially.
• adjective Unclear; vague.
• adjective Lacking precise limits.
• adjective Uncertain; undecided.

from The Century Dictionary.

• In grammar, not such as to make definite or determinate the person, thing, place, time, or manner in question: applied to certain adjectives, pronouns, and adverbs, as the indefinite article (see article, 11), any, some, such, anywhere, anyhow, otherwise, and to certain tenses of verbs, as the Greek aorist (which means ‘indefinite’) and the simple past in English.
• Not definite; not defined; not precise; vague: as, an indefinite time, proposition, term, or sensation.
• Infinite in number. The term was introduced by Pascal. Descartes distinguished between the indefinite, which has no particular limit, and the infinite, which is incomparably greater than anything having a limit. The distinction is considered as highly important by many metaphysicians.
• Specifically, in botany, uncertain in number or too great to be easily counted: for example, the stamens when more than 10, and not clearly in multiples of the ground number of the flower, are said to be indefinite.
• In logic, indeterminate in logical quantity; not distinguishing between “some” and “all.”

from the GNU version of the Collaborative International Dictionary of English.

• adjective Not definite; not limited, defined, or specified; not explicit; not determined or fixed upon; not precise; uncertain; vague; confused; obscure
• adjective Having no determined or certain limits; large and unmeasured, though not infinite; unlimited.
• adjective rare Boundless; infinite.
• adjective (Bot.) Too numerous or variable to make a particular enumeration important; -- said of the parts of a flower, and the like. Also, indeterminate.
• adjective (Gram.) the word a or an, used with nouns to denote any one of a common or general class.
• adjective (Bot.) See Indeterminate inflorescence, under Indeterminate.
• adjective (Logic) a statement whose subject is a common term, with nothing to indicate distribution or nondistribution; as, Man is mortal.
• adjective (Logic) a negative term; as, the not-good.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• adjective Without limit; forever, or until further notice; not definite.
• adjective Vague or unclear.
• adjective Undecided or uncertain.
• adjective mathematics An integral without specified limits.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• adjective not decided or not known
• adjective vague or not clearly defined or stated