harness

American  

[hahr-nis] / ˈhɑr nɪs /

noun

1. the combination of straps, bands, and other parts forming the working gear of a draft animal.

2. (on a loom) the frame containing heddles through which the warp is drawn and which, in combination with another such frame or other frames, forms the shed and determines the woven pattern.

3. the equipment, as straps, bolts, or gears, by which a large bell is mounted and rung.

4. Electricity. wiring harness.

5. armor for persons or horses.

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verb (used with object)

1. to put a harness on (a horse, donkey, dog, etc.); attach by a harness, as to a vehicle.

2. to bring under conditions for effective use; gain control over for a particular end.

   to harness water power; to harness the energy of the sun.

   Synonyms:

   exploit, utilize, manage, control

3. Archaic. to array in armor or equipments of war.

idioms

1. in double harness. double harness.

2. in harness,

   1. engaged in one's usual routine of work.

      After his illness he longed to get back in harness.

   2. together as cooperating partners or equals.

      Joe and I worked in harness on our last job.

harness British  

/ ˈhɑːnɪs /

noun

1. an arrangement of leather straps buckled or looped together, fitted to a draught animal in order that the animal can be attached to and pull a cart

2. something resembling this, esp for attaching something to the body

   a parachute harness

3. mountaineering an arrangement of webbing straps that enables a climber to attach himself to the rope so that the impact of a fall is minimized

4. the total system of electrical leads for a vehicle or aircraft

5. weaving the part of a loom that raises and lowers the warp threads, creating the shed

6. archaic armour collectively

7. at one's routine work

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verb

1. to put harness on (a horse)

2. (usually foll by to) to attach (a draught animal) by means of harness to (a cart, etc)

3. to control so as to employ the energy or potential power of

   to harness the atom

4. to equip or clothe with armour

harness More Idioms  

1. see die with one's boots on (in harness) in harness.

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Other Word Forms

• harness-like adjective
• harnesser noun
• harnessless adjective
• harnesslike adjective
• reharness verb (used with object)
• well-harnessed adjective

Etymology

Origin of harness

First recorded in 1250–1300; Middle English harneis, herneis, from Old French herneis “baggage, equipment,” from Old Norse hernest (unrecorded) “provisions for an armed force,” equivalent to herr “army” ( harbor, herald ) + nest “provisions for a journey”

Example Sentences

A quantum computer uses qubits—shorthand for quantum bits—to harness the behavior of subatomic particles, which can exist in multiple states at once.

From The Wall Street Journal • Mar. 23, 2026

At the same time, scientists may be able to harness these mechanisms to support beneficial microbes and design targeted microbiome therapies.

From Science Daily • Mar. 13, 2026

Kay, played by Nicole Kidman, is newly back in harness as the chief medical officer of the Commonwealth of Virginia, a job she’d held before being pushed out some unspecified years earlier.

From Los Angeles Times • Mar. 10, 2026

Mitchell was on hand to test the harness and wires beforehand, and to help ensure Robbie's safety when it was her turn.

From BBC • Mar. 3, 2026

Some dogs pull and when they get tired they slack off but they keep enough pull on the harness tug so it appears they are working while they are really resting.

From "Woodsong" by Gary Paulsen

Related Words

• curb
• exploit
• mobilize
• tackle
• tame
• utilize