Noun

(en-noun)

Two similar or identical things taken together; often followed by of.

* {{quote-magazine, date=2013-06-14, author=(Jonathan Freedland)

, volume=189, issue=1, page=18, magazine=(The Guardian Weekly) , title= Obama's once hip brand is now tainted , passage=Where we once sent love letters in a sealed envelope, or stuck photographs of our children in a family album, now such private material is despatched to servers and clouds operated by people we don't know and will never meet. Perhaps we assume that our name, address and search preferences will be viewed by some unseen pair of corporate eyes, probably not human, and don't mind that much.}}

Two people in a relationship, partnership (especially sexual) or friendship.

Used with binary nouns (often in the plural to indicate multiple instances, since such nouns are plurale tantum)

A couple of working animals attached to work together, as by a yoke.

(cards) A poker hand that contains of two cards of identical rank, which cannot also count as a better hand.

(cricket) A score of zero runs (a duck) in both innings of a two-innings match

(baseball, informal) A double play, two outs recorded in one play

(baseball, informal) A doubleheader, two games played on the same day between the same teams

(slang) A pair of breasts

(Australia, politics) The exclusion of one member of a parliamentary party from a vote, if a member of the other party is absent for important personal reasons.

Two members of opposite parties or opinion, as in a parliamentary body, who mutually agree not to vote on a given question, or on issues of a party nature during a specified time.

There were two pairs on the final vote.

(archaic) A number of things resembling one another, or belonging together; a set.

* Charles Dickens

plunging myself into poverty and shabbiness and love in one room up three pair of stairs

* Beaumont and Fletcher

Two crowns in my pocket, two pair of cards.

(kinematics) In a mechanism, two elements, or bodies, which are so applied to each other as to mutually constrain relative motion; named in accordance with the motion it permits, as in turning pair'', ''sliding pair'', ''twisting pair .