—pairwise, adv.n.1. two identical, similar, or corresponding things that are matched for use together: a pair of gloves; a pair of earrings.2. something consisting of or regarded as having two parts or pieces joined together: a pair of scissors; a pair of slacks.3. two individuals who are similar or in some way associated: a pair of liars; a pair of seal pups.4. a married, engaged, or dating couple.5. two mated animals.6. a span or team: a pair of horses.7. Govt.a. two members on opposite sides in a deliberative body who for convenience, as to permit absence, arrange together to forgo voting on a given occasion.b. the arrangement thus made.8. Cards.a. two playing cards of the same denomination without regard to suit or color.b. pairs, two card players who are matched together against different contestants.10. Also called kinematic pair. Mech. two parts or pieces so connected that they mutually constrain relative motion.11. Philately. two postage stamps joined together either vertically or horizontally.12. a set or combination of more than two objects forming a collective whole: a pair of beads.v.t.13. to arrange or designate in pairs or groups of two: She paired dancers for the waltz contest.14. to form into a pair, as by matching, joining, etc.; match; couple: to pair freshly washed socks.15. (of animals) to cause to mate.v.i.17. to form a pair or pairs.18. to be a member of a pair.19. to match with or resemble another.20. to unite in close association with another, as in a business partnership, friendship, marriage, etc.21. (of animals) to mate.22. Govt. (in a deliberative body) to form or arrange a pair.[1250-1300; ME paire < OF < L paria, pl. (taken as fem. sing.) of par a pair. See PAR1]Syn. 1. PAIR, BRACE, COUPLE, SPAN, YOKE are terms for groups of two. PAIR is used of two things naturally or habitually associated in use, or necessary to each other to make a complete set: a pair of dice. It is used also of one thing composed of two similar and complementary parts: a pair of trousers. BRACE is a hunter's term, used of a pair of dogs, ducks, etc., or a pair of pistols or slugs: a brace of partridges.In COUPLE the idea of combination or interdependence has become greatly weakened; it may be used loosely for two of anything (a couple of apples), and even for more than two: I have to see a couple of people. SPAN is used of a matched pair of horses harnessed together side by side. YOKE applies to the two animals hitched together under a yoke for drawing and pulling: a yoke of oxen.Usage. When used without a modifier, PAIRS is the only possible plural: Pairs of skaters glided over the ice. When modified by a number, PAIRS is the more common form, especially referring to persons: Six pairs of masked dancers led the procession. The unmarked plural PAIR is used mainly in reference to inanimate objects or nonhumans: He has three pair (or pairs) of loafers. Two pair (or pairs) of barn owls have nested on our property.PAIR signifying two individuals can take either a singular or plural verb, but it is usually followed by a plural verb and referred to by a plural pronoun: The guilty pair have not been seen since their escape.In the sense "a set or combination of more than two objects forming a collective whole," PAIR occurs chiefly in fixed phrases: a pair of beads; a pair of stairs. This use is now somewhat old-fashioned. See also collective noun, couple./perdd/, adj.
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