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strength (strĕngkth, strĕngth, strĕnth)
1. The state or quality of being strong; physical power or capacity: the strength needed to lift a box.
2. The capacity to resist attack; impregnability: the strength of the ship's armor.
3. The capacity to resist strain or stress; durability: the strength of the cables.
4. The ability to deal with difficult situations or to maintain a moral or intellectual position: Does he have the strength to overcome such a tragedy?
a. The number of people constituting a normal or ideal organization: The police force has been at half strength since the budget cuts.
b. Capability in terms of numbers or resources: an army of fearsome strength.
a. An attribute or quality of particular worth or utility; an asset: Your easygoing nature is one of your strengths.
b. One that is regarded as the embodiment of protective or supportive power; a support or mainstay: Her family has been her strength in difficult times.
a. Degree of concentration, distillation, or saturation: What's the strength of that cleaning solution?
b. Operative effectiveness or potency: the strength of the drug.
c. Intensity, as of sound or light: the strength of the wind.
d. Intensity of emotion or belief: the strength of feeling among the voters.
e. Cogency or persuasiveness: the strength of his argument.
8. Effective or binding force; efficacy: the strength of an argument.
9. Firmness of or a continuous rising tendency in prices, as of a currency or market.
10. Games Power derived from the value of playing cards held.
on the strength of
On the basis of: She was hired on the strength of her computer skills.

[Middle English, from Old English strengthu.]

Synonyms: strength, power, might1, energy, force
These nouns denote the capacity to act or work effectively. Strength refers especially to physical, mental, or moral robustness or vigor: "enough work to do, and strength enough to do the work" (Rudyard Kipling).
Power is the ability to do something and especially to produce an effect: "I do not think the United States would come to an end if we lost our power to declare an Act of Congress void" (Oliver Wendell Holmes, Jr.)
Might often implies abundant or extraordinary power: "He could defend the island against the whole might of the German Air Force" (Winston S. Churchill).
Energy refers especially to a latent source of power: "The same energy of character which renders a man a daring villain would have rendered him useful to society, had that society been well organized" (Mary Wollstonecraft).
Force is the application of power or strength: "the overthrow of our institutions by force and violence" (Charles Evans Hughes).

Usage Note: Although the word strength is not spelled with a k, it is most often pronounced (strĕngkth), with a (k) sound inserted between the (ng) and the (th). This intrusive (k) occurs for a simple reason: In making the transition from the voiced velar nasal (ng) to the voiceless dental fricative (th), speakers naturally produce the voiceless velar stop (k), which is made at the same place in the mouth as (ng) but is voiceless like (th). Other words with intrusive consonants include warmth, which may sound like it is spelled warmpth, and prince, which may sound like prints. The pronunciation (strĕnth), which is made with (n) before (th), arises by the phonological process of assimilation. The velar (ng) moves forward in the mouth, becoming (n) before (th), which is made at the front of the mouth. Criticized in the past as sloppy, this pronunciation is now generally regarded as a standard, although less common, variant. The similar pronunciation of length is now also considered acceptable.

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. All rights reserved.

Indo-European & Semitic Roots Appendices

    Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

    Indo-European Roots

    Semitic Roots

    The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.