Etymology From Latin dēfīnītus, past participle of dēfīniō, whence also English define.
1
Having distinct limits.
definite dimensions; a definite measure; a definite period or interval
[…] elements combine in definite proportions […]1837, William Whewell, chapter 8, in History of the Inductive Sciences, volume 3, book 14, London: John W. Parker, page 145:
2
Free from any doubt.
definite knowledge
3
Determined; resolved; decided.
[…] idiots in this case of favour would Be wisely definite1611 April (first recorded performance), William Shakespeare, “The Tragedie of Cymbeline”, in Mr. William Shakespeares Comedies, Histories, & Tragedies […] (First Folio), London: […] Isaac Iaggard, and Ed[ward] Blount, published 1623, →OCLC, [Act I, scene vi]:
4
Human sciences, Linguistics, Sciences Designating an identified or immediately identifiable person or thing, or group of persons or things