1520s, “not precise, vague,” from Latin indefinitus “indefinite,” from in- “not, opposite of, without” (see in- (1)) + definitus, past participle of definire (see define). In reference to 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.” [Century Dictionary]
early 15c., “without settled limitation, boundless;” see indefinite + -ly (2).
“simple, uninflected form of a verb, expressing its general sense,” 1510s, from earlier use as an adjective (mid-15c.), from Late Latin infinitivus “unlimited, indefinite,” from Latin infinitus “not limited” (see infinite). “Indefinite” because not restricted by person or number. Related: Infinitival; infinitively.
1580s, the tense of Greek verbs that most closely corresponds to the simple past in English, from Greek aoristos (khronos) “indefinite (tense),” from aoristos “without boundaries, undefined, indefinite,” from assimilated form of a- “not” (see a- (3)) + horistos “limited, defined,” verbal adjective from horizein “to limit, define,” from horos “boundary, limit, border” (see horizon). Related: Aoristic.
Source: O
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