Complement vs. Auxiliary — What's the Difference?

Something that completes, makes up a whole, or brings to perfection

Giving assistance or support; helping.

The quantity or number needed to make up a whole

Acting as a subsidiary; supplementary

The full crew of personnel required to run a ship.

Held in or used as a reserve

Either of two parts that complete the whole or mutually complete each other.

(Nautical) Equipped with a motor as well as sails.

An angle related to another so that the sum of their measures is 90°.

(Grammar) Of, relating to, or being an auxiliary verb.

(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.

An individual or group that assists or functions in a supporting capacity

(Music) An interval that completes an octave when added to a given interval.

A member of a foreign body of troops serving a country in war.

(Immunology) A complex system of proteins found in blood plasma that are sequentially activated and play various roles in the immune response, including lysing bacterial cell membranes, making pathogens more susceptible to phagocytes, and recruiting inflammatory cells to sites of infection or injury. Also called alexin.

(Grammar) An auxiliary verb.

Mathematics & Logic For a universal set, the set of all elements in the set that are not in a specified subset.

A sailing vessel equipped with a motor.

A complementary color.

A vessel, such as a supply ship or a tug, that is designed for and used in instances and services other than combat.

To serve as a complement to

Helping; giving assistance or support.

Something (or someone) that completes; the consummation.

Supplementary or subsidiary.

(obsolete) The act of completing something, or the fact of being complete; completion, completeness, fulfilment.

Held in reserve for exceptional circumstances.

The totality, the full amount or number which completes something.

(nautical) Of a ship, having both sails and an engine.

(obsolete) Something which completes one's equipment, dress etc.; an accessory.

(grammar) Relating to an auxiliary verb.

(nautical) The whole working force of a vessel.

A person or group that acts in an auxiliary manner.

(heraldry) Fullness (of the moon).

A sailing vessel equipped with an engine.

An angle which, together with a given angle, makes a right angle.

(grammar) An auxiliary verb.

Something which completes, something which combines with something else to make up a complete whole; loosely, something perceived to be a harmonious or desirable partner or addition.

A marching band colorguard.

A word or group of words that completes a grammatical construction in the predicate and that describes or is identified with the subject or object.

Conferring aid or help; helping; aiding; assisting; subsidiary; as auxiliary troops.

(music) An interval which, together with the given interval, makes an octave.

A helper; an assistant; a confederate in some action or enterprise.

(optics) The color which, when mixed with the given color, gives black (for mixing pigments) or white (for mixing light).

A verb which helps to form the voices, modes, and tenses of other verbs; - called, also, an auxiliary verb; as, have, be, may, can, do, must, shall, and will, in English; être and avoir, in French; avere and essere, in Italian; estar and haber, in Spanish.

(set theory) Given two sets, the set containing one set's elements that are not members of the other set (whether a relative complement or an absolute complement).

A quantity introduced for the purpose of simplifying or facilitating some operation, as in equations or trigonometrical formulæ.

(immunology) One of several blood proteins that work with antibodies during an immune response.

Someone who acts as assistant

(logic) An expression related to some other expression such that it is true under the same conditions that make other false, and vice versa.

Functioning in a subsidiary or supporting capacity;

(electronics) A voltage level with the opposite logical sense to the given one.

Relating to something that is added but is not essential;

(computing) A bit with the opposite value to the given one; the logical complement of a number.

The diminished radix complement of a number; the nines' complement of a decimal number; the ones' complement of a binary number.

The radix complement of a number; the two's complement of a binary number.

The numeric complement of a number.

(genetics) 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.

Obsolete spelling or misspelling of compliment. should this be at a different ety?

(biochemistry) alexin

(economics) complementary good

To complete, to bring to perfection, to make whole.

To provide what the partner lacks and lack what the partner provides, thus forming part of a whole.

To change a voltage, number, color, etc. to its complement.

(obsolete) Old form of compliment

That which fills up or completes; the quantity or number required to fill a thing or make it complete.

That which is required to supply a deficiency, or to complete a symmetrical whole.

Full quantity, number, or amount; a complete set; completeness.

A second quantity added to a given quantity to make it equal to a third given quantity.

Something added for ornamentation; an accessory.

The whole working force of a vessel.

The interval wanting to complete the octave; - the fourth is the complement of the fifth, the sixth of the third.

A compliment.

To supply a lack; to supplement.

To compliment.

A word or phrase used to complete a grammatical construction

A complete number or quantity;

Number needed to make up whole force;

Something added to complete or make perfect;

One of a series of enzymes in the blood serum that are part of the immune response

Either of two parts that mutually complete each other

Make complete or perfect; supply what is wanting or form the complement to;