1. (n.) An impulse; an incentive; an impelling force; as, an impetus for change or correction\; a property possessed by a moving body in virtue of its weight and its motion; the force with which any body is driven or impelled; momentum.

2. (n.) Fig.: Impulse; incentive; vigor; force.

3. (n.) The altitude through which a heavy body must fall to acquire a velocity equal to that with which a ball is discharged from a piece.

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