• 2 (number), two of something
• Topological pair, an inclusion of topological spaces.
• Au pair, a work agreement
• Couple, various senses for two joined things
• Even number, in roulette etc.
• Ordered pair, in Mathematics and set theory
• Twisted pair, a couple of electric wires twisted together
• Pair (parliamentary convention), matching of members unable to attend, so as not to change the voting margin
• pair, the French equivalent of peer, holder of a French Pairie, French high title roughly equivalent to a member of the British peerage
• pair, a member of the Prussian House of Lords
• Pair (Cricket): "getting a pair" means being out for 0 in both innings of a match
• A handshaking process in Bluetooth communications
• P_air, Pressure of air in a system

See also

• Pairing
• Pear - fruit
• Pare - Tanzanian ethnic group
• Paired test in statistical hypothesis testing