from The American Heritage® Dictionary of the English Language, 4th Edition

  • n. A statement conveying fundamental character.
  • n. A statement of the meaning of a word, phrase, or term, as in a dictionary entry.
  • n. The act or process of stating a precise meaning or significance; formulation of a meaning.
  • n. The act of making clear and distinct: a definition of one's intentions.
  • n. The state of being closely outlined or determined: "With the drizzle, the trees in the little clearing had lost definition” ( Anthony Hyde).
  • n. A determination of outline, extent, or limits: the definition of a President's authority.
  • n. The clarity of detail in an optically produced image, such as a photograph, effected by a combination of resolution and contrast.
  • n. The degree of clarity with which a televised image or broadcast signal is received.

from Wiktionary, Creative Commons Attribution/Share-Alike License

  • n. A statement of the meaning of a word or word group or a sign or symbol (dictionary definitions).
  • n. A statement expressing the essential nature of something; formulation
  • n. The action or process of defining.
  • n. The act of defining; determination of the limits.
  • n. A product of defining.
  • n. The action or power of describing, explaining, or making definite and clear.
  • n. Clarity of visual presentation, distinctness of outline or detail.
  • n. Clarity, especially of musical sound in reproduction.
  • n. Sharp demarcation of outlines or limits.
  • n. The degree to which individual muscles are distinct on the body.
  • n. A statement which provides a previous delcaration with a value or body of a subroutine (in the case of function).

from the GNU version of the Collaborative International Dictionary of English

  • n. The act of defining; determination of the limits.
  • n. Act of ascertaining and explaining the signification; a description of a thing by its properties; an explanation of the meaning of a word or term
  • n. Description; sort.
  • n. An exact enunciation of the constituents which make up the logical essence.
  • n. Distinctness or clearness, as of an image formed by an optical instrument; precision in detail.

from The Century Dictionary and Cyclopedia

  • n. The determination of the limits or outlines of a thing; a marking out; the state of being clearly marked out or outlined; specifically, in optics, the defining power of a lens—that is, its ability to give a clear, distinct image of an object in all its important details. This depends upon the freedom of the lens from spherical and chromatic aberration.
  • n. The act of stating the signification of a word or phrase, or the essential properties of a thing.
  • n. A statement of the signification of a word or phrase, or of what is essential to the conception of any given thing; an explanation of how any given kind is distinguished from all other kinds.

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

  • n. a concise explanation of the meaning of a word or phrase or symbol
  • n. clarity of outline


Middle English diffinicioun, from Old French definition, from Latin dēfīnītiō, dēfīnītiōn-, from dēfīnītus, past participle of dēfīnīre, to define; see define.
(American Heritage® Dictionary of the English Language, Fourth Edition)
From Middle English diffinicioun, from Middle French definition, from Latin dēfīnītiō, from dēfīniō. (Wiktionary)


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  • It is rather amusing at times, once you get used to it, Asativum. :-)

    November 21, 2007

  • If only the world were so black and white.

    November 21, 2007

  • Gotcha. So it either happens or it doesn't. I can rest easy now.

    November 21, 2007

  • The nice people at Princeton provide them.

    Someday there'll be a way to add definitions to words not covered by the integrated dictionary, or a way to collaboratively promote comments to definition status. Not sure which day, though. I wouldn't hold your breath :-)

    November 21, 2007

  • So how does one get that nifty definition next to a word?

    November 21, 2007