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

  • n. Something that completes, makes up a whole, or brings to perfection.
  • n. The quantity or number needed to make up a whole: shelves with a full complement of books.
  • n. Either of two parts that complete the whole or mutually complete each other.
  • n. An angle related to another so that the sum of their measures is 90°.
  • n. Grammar A word or words used to complete a predicate construction, especially the object or indirect object of a verb; for example, the phrase to eat ice cream in We like to eat ice cream.
  • n. Music An interval that completes an octave when added to a given interval.
  • n. The full crew of officers and enlisted personnel required to run a ship.
  • n. Immunology A complex system of proteins found in normal blood plasma that combines with antibodies to destroy pathogenic bacteria and other foreign cells. Also called alexin.
  • n. Mathematics & Logic For a universal set, the set of all elements in the set that are not in a specified subset.
  • n. A complementary color.
  • transitive v. To serve as a complement to: Roses in a silver bowl complement the handsome cherry table.

from Wiktionary, Creative Commons Attribution/Share-Alike License

  • n. A voltage level with the opposite logical sense to the given one.
  • n. A bit with the opposite value to the given one; the logical complement of a number.
  • n. The diminished radix complement of a number; the nines' complement of a decimal number; the ones' complement of a binary number.
  • n. The radix complement of a number; the two's complement of a binary number.
  • n. The numeric complement of a number.
  • n. A nucleotide sequence in which each base is replaced by the complementary base of the given sequence: adenine (A) by thymine (T) or uracil (U), cytosine (C) by guanine (G), and vice versa.
  • n. Obsolete spelling of compliment.
  • v. To complete, to bring to perfection, to make whole.
  • v. To provide what the partner lacks and lack what the partner provides.
  • v. To change a voltage, number, color, etc. to its complement.
  • v. Obsolete form of compliment..

from the GNU version of the Collaborative International Dictionary of English

  • n. That which fills up or completes; the quantity or number required to fill a thing or make it complete.
  • n. That which is required to supply a deficiency, or to complete a symmetrical whole.
  • n. Full quantity, number, or amount; a complete set; completeness.
  • n. A second quantity added to a given quantity to make it equal to a third given quantity.
  • n. Something added for ornamentation; an accessory.
  • n. The whole working force of a vessel.
  • n. The interval wanting to complete the octave; -- the fourth is the complement of the fifth, the sixth of the third.
  • n. A compliment.
  • transitive v. To supply a lack; to supplement.
  • transitive v. To compliment.

from The Century Dictionary and Cyclopedia

  • To add a complement to; complete or fill up.
  • n. Full quantity or number; full amount; complete allowance: as, the company had its complement of men; the ship had its complement of stores.
  • n. Perfect state; fullness; completeness.
  • n. What is needed to complete or fill up some quantity or thing; that which anything lacks of completeness or fullness: as, the complement of an angle (which see, below).
  • n. In music, the interval formed by the higher note and the note an octave above the lower note of a given simple interval.
  • n. That which is added, not as necessary, but as ornamental; an accessory; an appendage.
  • n. Compliment: a word of the same ultimate origin and formerly of the same spelling. See compliment.
  • n. An accomplishment.
  • n. In physiol. chem., same as alexin. See the extract.

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

  • n. something added to complete or embellish or make perfect
  • n. either of two parts that mutually complete each other
  • n. one of a series of enzymes in the blood serum that are part of the immune response
  • n. a word or phrase used to complete a grammatical construction
  • n. number needed to make up a whole force
  • v. make complete or perfect; supply what is wanting or form the complement to
  • n. a complete number or quantity


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

Middle English, from Old French, from Latin complēmentum, from complēre, to fill out; see complete.

from Wiktionary, Creative Commons Attribution/Share-Alike License

From Latin complementum ("that which fills up or completes"), from complere ("to fill up, complete"), with some senses from Old French.


  • As the objective complement generally denotes what the receiver of the act is made to be, in fact or in thought, it is sometimes called the _factitive complement_ or the _factitive object_ (Lat. _facere_, to make).

    Higher Lessons in English A work on english grammar and composition

  • The complement is to separate a fish open as good as nail it to a board, which is afterwards placed in a immeasurable open grate to cook, as good as sizzle, as good as smell customarily smashing good.

    Archive 2009-11-01

  • And if we’re testing “innate” intelligence, we’re obviously testing the wrong thing (s), because the freakin’ genetic complement is (essentially) unchanged throughout life. clarice: (2) You suggest we have enough examples of bad nurturing and we should do something about that.

    The Volokh Conspiracy » 1. Science, Faith, and Not Ruling Out Possibilities

  • Because a complement is not required/possible after an adverb?

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  • CINCINNATI — Wide receiver Antonio Bryant was released on Sunday by the Cincinnati Bengals, who signed him to a four-year, $28 million deal last March thinking he would be their long-term complement to Chad Ochocinco.

    Antonio Bryant Released, But Still Makes $7 Million

  • A complement is needed to second-year CB Darrelle Revisy.

    '08 NFL draft: AFC team needs

  • If the subject complement is a personal pronoun, it must be in the nominative (subject) case.

    Grafik review

  • It may be asked why the action of the complement is so fleeting in the white corpuscles, when it lasts much longer in the humours taken from the organism, such as blood serum.

    Ilya Mechnikov - Nobel Lecture

  • Do not think that as the action of the complement is only manifest while the white corpuscles are alive, this is purely a vital phenomenon.

    Ilya Mechnikov - Nobel Lecture

  • The synergistic coordination between the function released through the vegetative nervous system and the somatomotor complement is manifest.

    Walter Hess - Nobel Lecture


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