(computing) To push the button on a mouse twice in quick succession in order to perform a different task than would be performed from a single-click or triple-click.

(basketball) A violation committed by dribbling for a second time without giving up possession of the ball.

(physical chemistry) A covalent bond in which two electron pairs (instead of the usual one) are shared between two atoms; most common between carbon atoms and carbon, oxygen or nitrogen atoms, but several other forms are known.

An extra check or verification made a second time, usually with additional caution or attention. / (chess, uncountable) A check delivered by two pieces simultaneously.

To check again; to check with extra caution or attention; to verify or make sure.

The largest stringed instrument of the violin family. / The deepest of all male voices.

A film stand-in for an actor, in scenes not involving the face, especially during scenes of nudity, or of dangerous activity.

(bridge) A double, usually indicating strength and a desire to play the hand; partner is expected to "take out" by making a bid.

An abrupt movement, used, for example, as a comical reaction to a surprising sight, in which someone casually sees something, briefly stops looking at it, realizes what it is, and snaps attention back to it with an expression of surprise or disbelief.

(astronomy) Two stars which form a stellar system, such that they orbit the point of equilibrium of their gravitational fields; a binary star.