definitive

The definition of definitive is something that is settled in a final way or something that is authoritative.

(adjective)

An example of something that would be described as definitive is a conclusive decision made by an authority figure.
A use of the adjective definitive would be a definitive history book, which would be a complete history on a specific subject.

See definitive in Webster's New World College Dictionary

adjective

that decides or settles in a final way; decisive; conclusive: a definitive answer
most nearly complete and accurate; authoritative: a definitive biography
serving to define; limiting or distinguishing precisely: definitive details
designating or of a postage stamp for regular use, issued for an unlimited period

Origin: ME diffinitif < OFr definitif < L definitivus < pp. of definire, define

noun

a definitive postage stamp

Related Forms:

See definitive in American Heritage Dictionary 4

adjective

Precisely defined or explicit.
Supplying or being a final settlement or decision; conclusive. See Synonyms at decisive.
Authoritative and complete: a definitive biography. See Usage Note at definite.
Biology Fully formed or developed, as an organ or structure.

noun
Grammar

A word that defines or limits, such as the definite article or a demonstrative pronoun.

Related Forms: