(nautical) The practice of having two alternate watches aboard a ship or vessel.

Forty plus two; the cardinal number following forty-one and preceding forty-three.

(mechanical) Of or relating to a design of internal combustion engine, the working cycle of which is completed during two strokes of the piston.

A two-stroke engine. / A vehicle or machine powered by a two-stroke engine. / The fuel used in a two-stroke engine. / (Australia, slang) Coca-Cola.

The cardinal number immediately following sixty-one and preceding sixty-three.

(computing) The number obtained by complementing every bit of a given number and adding one. A number and its complement add to 2ⁿ, where n is the word size of the machine.

(Australia, New Zealand, games) A game of chance, played by betting on the outcome of two pennies thrown in the air.

(of a printed document) Having two document pages per printed page.

(manner, of travel on a motorcycle) With two people aboard.

(baseball) A two-seam fastball.