noun

motive

MOH-tiv/ˈməʊtɪv/

A reason for doing something.

The parent's motive for repairing the bicycle is the child's future enjoyment.

A parent works carefully repairing a bicycle while thinking of their child happily riding it, reason motivating action.

Etymology

Something “moving or impelling” became an inward force that moves a person to act. A motive is thus a reason understood as a psychological driving force.

In context

Libertarianism.org13:55

Mandeville was wrong to equate self-interest with Vice since self-love may frequently be a virtuous motive of action

Excursions, Ep. 155: Self-Interest and Social Order: Bernard Mandeville v. Francis Hutcheson

More examples

The detective tries to establish a motive for the theft.
I trust his advice, but I question his motives.
She offers to help without any ulterior motive.

Forms

motive · motives

motivate verb — Give someone a reason to act.

motivation noun — The desire or drive to take action.

Similar words

reason: Reason is broader and need not explain someone's actions.
purpose: Purpose emphasizes the intended result rather than the underlying reason.
incentive: Incentive emphasizes a reward or benefit that encourages action.