To exercise influence over; to suggest or dictate the behavior of.
(construed with for) To design (an experiment) so that the effects of one or more variables are reduced or eliminated.
To verify the accuracy of (something or someone, especially a financial account) by comparison with another account.
(obsolete) To call to account, to take to task, to challenge.
To hold in check, to curb, to restrain.

An influence or authority over something.
The method and means of governing the performance of any apparatus, machine or system, such as a lever, handle or button.
Restraint or ability to contain one's movements or emotions, or self-control.
A security mechanism, policy, or procedure that can counter system attack, reduce risks, and resolve vulnerabilities; a safeguard or countermeasure.
A means of monitoring for, and triggering intervention in, activities that are not going according to plan.
A control group or control experiment.
A duplicate book, register, or account, kept to correct or check another account or register.
An interface element that a computer user interacts with, such as a window or a text box (abbreviated Ctrl).
Any of the physical factors determining the climate of a place, such as latitude, distribution of land and water, altitude, exposure, prevailing winds, permanent high- or low-barometric-pressure areas, ocean currents, mountain barriers, soil, and vegetation.
A construction in which the understood subject of a given predicate is determined by an expression in context. See control.
A spirit that takes possession of a psychic or medium and allows other spirits to communicate with the living.
A checkpoint along an audax route.