pow·er (pou??r)n.1. a. The ability or capacity to act or do something effectively: Is it in your power to undo this injustice?b. often powers A specific capacity, faculty, or aptitude: her powers of concentration.2. a. Physical strength or force exerted or capable of being exerted: the power of the waves. See Synonyms at strength.b. Effectiveness at moving one’s emotions or changing how one thinks: a novel of great power.3. a. The ability or official capacity to exercise control; authority: How long has that party been in power?b. The military strength or economic or political influence of a nation or other group: That country projects its power throughout the region.c. A country, nation, or other political unit having great influence or control over others: the western powers.4. a. A supernatural being: the powers of evil.b. powers Christianity The sixth of the nine orders of angels in medieval angelology.5. a. The energy or motive force by which a physical system or machine is operated: turbines turned by steam power; a sailing ship driven by wind power.b. The capacity of a system or machine to operate: a vehicle that runs under its own power.c. Electrical or mechanical energy, especially as used to assist or replace human energy.d. Electricity supplied to a home, building, or community: a storm that cut off power to the whole region.6. Physics The rate at which work is done, expressed as the amount of work per unit time and commonly measured in units such as the watt and horsepower.7. Electricity a. The product of applied potential difference and current in a direct-current circuit.b. The product of the effective values of the voltage and current with the cosine of the phase angle between current and voltage in an alternating-current circuit.8. Mathematics a. See exponent.b. The number of elements in a finite set.9. Statistics In a statistical test, the probability of correctly rejecting the null hypothesis when it is false.10. A measure of the magnification of an optical instrument, such as a microscope or telescope.11. Chiefly Upper Southern US A large number or amount. See Note at powerful.12. Archaic An armed force.adj.1. Of or relating to political, social, or economic control: a power struggle; a power base.2. Operated with mechanical or electrical energy in place of bodily exertion: a power tool; power car windows.3. Of or relating to the generation or transmission of electricity: power companies; power lines.4. Informal Of or relating to influential business or professional practices: a pinstriped suit with a power tie; met with high-level executives at a power breakfast.tr.v. pow·ered, pow·er·ing, pow·ers To supply with power, especially mechanical or electrical power.Idiom: powers that be Those who hold effective power in a system or situation: a plan vetoed by the powers that be.[Middle English, from Old French pooir, to be able, power, from Vulgar Latin *pot?re, to be able, from Latin potis, able, powerful; see poti- in Indo-European roots.]American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.power (?pa??) n1. ability or capacity to do something2. (often plural) a specific ability, capacity, or faculty3. political, financial, social, etc, force or influence4. (Government, Politics & Diplomacy) control or dominion or a position of control, dominion, or authority5. (Government, Politics & Diplomacy) a state or other political entity with political, industrial, or military strength6. a person who exercises control, influence, or authority: he’s a power in the state. 7. a prerogative, privilege, or liberty8. (Law) a. legal authority to act, esp in a specified capacity, for anotherb. the document conferring such authority9. (Military) a. a military forceb. military potential10. (Mathematics) maths a. the value of a number or quantity raised to some exponentb. another name for exponent411. (Statistics) statistics the probability of rejecting the null hypothesis in a test when it is false. The power of a test of a given null depends on the particular alternative hypothesis against which it is tested12. (General Physics) physics engineering a measure of the rate of doing work expressed as the work done per unit time. It is measured in watts, horsepower, etc. Symbol: P 13. (Electronics) a. the rate at which electrical energy is fed into or taken from a device or system. It is expressed, in a direct-current circuit, as the product of current and voltage and, in an alternating-current circuit, as the product of the effective values of the current and voltage and the cosine of the phase angle between them. It is measured in wattsb. (as modifier): a power amplifier. 14. the ability to perform work15. (Mechanical Engineering) a. mechanical energy as opposed to manual labourb. (as modifier): a power mower. 16. a particular form of energy: nuclear power. 17. (General Physics) a. a measure of the ability of a lens or optical system to magnify an object, equal to the reciprocal of the focal length. It is measured in dioptresb. another word for magnification18. informal a large amount or quantity: a power of good. 19. (Theology) (plural) the sixth of the nine orders into which the angels are traditionally divided in medieval angelology20. in one’s power (often foll by an infinitive) able or allowed (to)21. in someone’s power under the control or sway of someone22. the powers that be the established authority or administrationvb (tr) 23. to give or provide power to24. (Mechanical Engineering) to fit (a machine) with a motor or engine25. (intr) slang to travel with great speed or force[C13: from Anglo-Norman poer, from Vulgar Latin pot?re (unattested), from Latin posse to be able]Collins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014pow?er (?pa? ?r) n. 1. ability to do or act; capability of doing or accomplishing something. 2. political or national strength. 3. great or marked ability to do or act; strength; might; force. 4. the possession of control or command over others; authority; ascendancy: power over people’s minds. 5. political ascendancy or control in the government of a country, state, etc. 6. legal ability, capacity, or authority. 7. delegated authority; authority granted to a person or persons in a particular office or capacity: the powers of the president. 8. a document or written statement conferring legal authority. 9. a person or thing that possesses or exercises authority or influence. 10. a state or nation having international authority or influence. 11. a military or naval force. 12. Often, powers. a deity; divinity: the heavenly powers. 13. powers, an order of angels. Compare angel (def. 1). 14. Physics. work done or energy transferred per unit of time. Symbol: P 15. mechanical energy as distinguished from hand labor: a loom driven by power. 16. a particular form of mechanical or physical energy: hydroelectric power. 17. energy, force, or momentum. 18. Math. a. the product obtained by multiplying a quantity by itself one or more times: The third power of 2 is 8. b. the exponent of an expression, as a in xa. 19. a. the magnifying capacity of a microscope, telescope, etc., expressed as the ratio of the diameter of the image to the diameter of the object. Compare magnification (def. 2). b. the reciprocal of the focal length of a lens. v.t. 20. to supply with electricity or other means of power. 21. to give power to; make powerful. 22. to inspire; spur. 23. (of a fuel, engine, or any source able to do work) to supply force to operate (a machine). 24. power up, to prepare to operate or do work: to power up a computer; powered up for the final match. adj. 25. operated or driven by a motor or electricity: a power mower; power tools. 26. operated by a procedure in which manual effort is supplemented or replaced by hydraulic, mechanical, or electric means: power brakes. 27. conducting electricity: a power cable. 28. Informal. expressing power; involving or characteristic of those having authority or influence: a power breakfast. Idioms: the powers that be, those in supreme command; the authorities. [1250?1300; Middle English pouer(e), poer(e)