|a calculus or concretion found in the stomach or intestines of certain animals, esp. ruminants, formerly reputed to be an effective remedy for poison.|
|a stew of meat, vegetables, potatoes, etc.|
|—vb , -trols, -trolling, -trolled|
|1.||to command, direct, or rule: to control a country|
|2.||to check, limit, curb, or regulate; restrain: to control one's emotions; to control a fire|
|3.||to regulate or operate (a machine)|
|4.||to verify (a scientific experiment) by conducting a parallel experiment in which the variable being investigated is held constant or is compared with a standard|
|5.||a. to regulate (financial affairs)|
|b. to examine and verify (financial accounts)|
|6.||to restrict or regulate the authorized supply of (certain substances, such as drugs)|
|7.||power to direct or determine: under control; out of control|
|8.||a means of regulation or restraint; curb; check: a frontier control|
|9.||(often plural) a device or mechanism for operating a car, aircraft, etc|
|10.||a standard of comparison used in a statistical analysis or scientific experiment|
|11.||a. a device that regulates the operation of a machine. A dynamic control is one that incorporates a governor so that it responds to the output of the machine it regulates|
|b. (as modifier): control panel; control room|
|12.||spiritualism an agency believed to assist the medium in a séance|
|13.||Also called: control mark a letter, or letter and number, printed on a sheet of postage stamps, indicating authenticity, date, and series of issue|
|14.||one of a number of checkpoints on a car rally, orienteering course, etc, where competitors check in and their time, performance, etc, is recorded|
|[C15: from Old French conteroller to regulate, from contrerolle duplicate register, system of checking, from contre-|
control con·trol (kən-trōl')
v. con·trolled, con·trol·ling, con·trols
To verify or regulate a scientific experiment by conducting a parallel experiment or by comparing with another standard.
To hold in restraint; check.
A standard of comparison for checking or verifying the results of an experiment.
An individual or group used as a standard of comparison in a control experiment.
|control (kən-trōl') Pronunciation Key
A standard of comparison for checking or verifying the results of an experiment. In an experiment to test the effectiveness of a new drug, for example, one group of subjects (the control group) receives an inactive substance or placebo , while a comparison group receives the drug being tested.