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1. Chiefly hunting or coursing
a. a pair of collars joined by a leash, used to attach hounds to one another
b. two hounds joined in this way
c. the unit of reckoning for hounds in a pack
2. Mechanics a pair of equal and opposite parallel forces that have a tendency to produce rotation with a torque or turning moment equal to the product of either force and the perpendicular distance between them
3. Physics
a. two dissimilar metals, alloys, or semiconductors in electrical contact, across which a voltage develops
b. two dissimilar metals or alloys in electrical contact that when immersed in an electrolyte act as the electrodes of an electrolytic cell
Collins Discovery Encyclopedia, 1st edition © HarperCollins Publishers 2005


A system of two parallel forces of equal magnitude and opposite sense. Under a couple's action a rigid body tends only to rotate about a line normal to the couple's plane. This tendency reflects the vector properties of a couple.

The total force of a couple is zero. The total moment C of a couple is identical about any point. Accordingly, C is the moment of either force about a point on the other and is perpendicular to the couple's plane. See Resultant of forces, Statics

The moment of a couple about a directed line is the component of its total moment in the line's direction. Couples are equivalent whose total moments are equal.

McGraw-Hill Concise Encyclopedia of Physics. © 2002 by The McGraw-Hill Companies, Inc.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.



a system of two forces P and P’ acting on a rigid body that are equal to each other in absolute value, are parallel, and are opposite in direction—that is, P’ = – P (see Figure 1). A couple has no resultant. In other words, its action on a body cannot be mechanically equivalent to the action of any single force; accordingly, a couple cannot be balanced by a single force.

The distance l between the lines of action of the two forces is called the arm of the couple. The effect of a couple’s action on a body is described by the couple’s moment, which is represented by a vector M equal in absolute value to the quantity Pl and perpendicular to the couple’s plane on the side where the rotation

Figure 1

caused by the couple appears to be counterclockwise in a right-handed coordinate system. A basic property of a couple is that the effect of its action on a given body is not changed if the couple is shifted anywhere in its plane or in a plane parallel to its plane. In addition, if the absolute value of the forces of the couple and the length of the arm are changed while the moment of the couple is kept fixed, the effect on the body is not changed. Thus the moment of a couple can be regarded as applied to any point of the body. If two couples have identical moments M and are applied to the same body, they are mechanically equivalent to each other. Any system of couples that are applied to a given body is mechanically equivalent to a single couple having a moment equal to the geometric sum of the moment vectors of the couples. If the geometric sum of the moment vectors of a system of couples is equal to zero, the system is balanced.

S. M. TARG [19–4–85–3]

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.


Joining of two molecules.
To connect two circuits so signals are transferred from one to the other.
Two metals placed in contact, as in a thermocouple.
To connect with a coupling, such as of two belts or two pipes.
A system of two parallel forces of equal magnitude and opposite sense.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.


Two equal and opposite parallel forces, with different lines of action, tending to produce rotation of a body; their moment equals the product of the magnitude of one of the forces and the perpendicular distance between them.
McGraw-Hill Dictionary of Architecture and Construction. Copyright © 2003 by McGraw-Hill Companies, Inc.
References in classic literature ?
"I think there will be very tolerable room for ten couple."
It would be a disappointment to my fatherand altogetherI do not know thatI am rather of opinion that ten couple might stand here very well."
Ten couple, in either of the Randalls rooms, would have been insufferable!Dreadful!I felt how right you were the whole time, but was too anxious for securing any thing to like to yield.
'I have now said all I have to say: except that this young couple parted, firmly, though not without tears and sorrow, on the evening when you last saw them together.'
There were few couples on the floor when they arrived at the pavilion, and the two girls essayed the first waltz together.
She glanced at Bert, dancing "tough" with Mary, caroming down the long floor with more than one collision with the increasing couples. Graceful himself in his slender, tall, lean-stomached way, Bert was accounted a good dancer; yet Saxon did not remember ever having danced with him with keen pleasure.
I think there is nothing more pathetic than to see one of these poor old childless couples taking a menagerie of yelping little worthless dogs to their hearts; and then adding some cursing and squawking parrots and a jackass-voiced macaw; and next a couple of hundred screeching songbirds, and presently some fetid guinea pigs and rabbits, and a howling colony of cats.
There was much shaking of hands mingled with "God bless you's" and other good wishes to the four couples, at the churchyard gate, Mr.
Furthermore, even at the time I was born, there were several faithful couples that lived in the trees in the neighborhood of my mother.
The couple owns an online forex trading company - VIP Portal - based in Limuru town, where thousands of people lost more than Sh1 billion after the couple promised to double the deposits.
The immigration officials handed over the couple to the Central Crime Branch (CCB) of police who launched a search for two people, who arranged the fake passports for Vijayan, 35, and Yasodha, 33, hailing from Vavuni Kulam in Sri Lanka.
Rather, it should be a thing of peace and joy for couples involved and their relatives.