vector

American  

[vek-ter] / ˈvɛk tər /

noun

1. Mathematics.

   1. a quantity possessing both magnitude and direction, represented by an arrow the direction of which indicates the direction of the quantity and the length of which is proportional to the magnitude.

   2. such a quantity with the additional requirement that such quantities obey the parallelogram law of addition.

   3. such a quantity with the additional requirement that such quantities are to transform in a particular way under changes of the coordinate system.

   4. any generalization of the above quantities.

2. the direction or course followed by an airplane, missile, or the like.

3. Biology.

   1. an insect or other organism that transmits a pathogenic fungus, virus, bacterium, etc.

   2. any agent that acts as a carrier or transporter, as a virus or plasmid that conveys a genetically engineered DNA segment into a host cell.

4. Computers. an array of data ordered such that individual items can be located with a single index or subscript.

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verb (used with object)

1. Aeronautics. to guide (an aircraft) in flight by issuing appropriate headings.

2. Aerospace. to change direction of (the thrust of a jet or rocket engine) in order to steer the craft.

vector British  

/ vɛkˈtɔːrɪəl, ˈvɛktə /

noun

1. Also called: polar vector.  maths a variable quantity, such as force, that has magnitude and direction and can be resolved into components that are odd functions of the coordinates. It is represented in print by a bold italic symbol: F or ̄F Compare pseudoscalar pseudovector scalar tensor

2. maths an element of a vector space

3. Also called: carrier.  pathol an organism, esp an insect, that carries a disease-producing microorganism from one host to another, either within or on the surface of its body

4. Also called: cloning vector.  genetics an agent, such as a bacteriophage or a plasmid, by means of which a fragment of foreign DNA is inserted into a host cell to produce a gene clone in genetic engineering

5. the course or compass direction of an aircraft

6. any behavioural influence, force, or drive

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verb

1. to direct or guide (a pilot, aircraft, etc) by directions transmitted by radio

2. to alter the direction of (the thrust of a jet engine) as a means of steering an aircraft

vector Scientific  

/ vĕk′tər /

1. A quantity, such as the velocity of an object or the force acting on an object, that has both magnitude and direction.

2. Compare scalar

3. An organism, such as a mosquito or tick, that spreads pathogens from one host to another.

4. A bacteriophage, plasmid, or other agent that transfers genetic material from one cell to another.

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vector Cultural  

1. In physics and mathematics, any quantity with both a magnitude and a direction. For example, velocity is a vector because it describes both how fast something is moving and in what direction it is moving. Because velocity is a vector, other quantities in which velocity is a factor, such as acceleration and momentum, are vectors also.

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Other Word Forms

• vectorial
  adjective
• vectorially
  adverb

Etymology

Origin of vector

First recorded in 1695–1705; from Latin: “carrier,” from vec- (variant stem of vehere “to carry”) + -tor -tor

Explanation

One definition of a vector is that of a carrier — it might be an insect like a mosquito that carries and transmits a bacterium or virus, or it might be some agent that carries genetically engineered DNA into a cell. Considering that the Latin word vector comes from the word vehere, which means "to carry," it's not surprising that the current use of the word also "carries" the same meaning. In fact, in computers, a vector is a method used to propagate a computer virus. However, the word vector is also used in various scientific areas, including mathematics, where it indicates something possessing both size and direction; and aeronautics, where it indicates a projectile's course.

Example Sentences

"Each new phase of Galkynysh so far tends to reinforce the Chinese vector rather than genuinely diversify it," Narymbetov said.

From Barron's • Apr. 21, 2026

Hurricanes turned out to be a vector for spreading the little winged bug.

From Slate • Apr. 20, 2026

"A novel aspect of the paper was our use of powerful mass spectrometry sequencing to identify molecular mimicry between the adenovirus vector protein and the PF4 culprit target," she says.

From Science Daily • Apr. 10, 2026

While high-dimensional vectors can be compressed through vector quantization, that technique comes with its own memory issues as it requires calculating and storing additional data, “partially defeating the purpose of vector quantization,” Google said.

From MarketWatch • Mar. 25, 2026

Nurse Mayinga seemed to be a vector for an explosive chain of lethal transmission in a crowded third-world city with a population of two million people.

From "The Hot Zone" by Richard Preston