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flex-
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pref.
Variant of flexi-.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. All rights reserved.
 
flex (flĕks)
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v. flexed, flex·ing, flex·es
v.tr.
1. To bend (something pliant or elastic).
2.
a. To bend (a joint).
b. To bend (a joint) repeatedly.
3.
a. To contract (a muscle, for example).
b. To move by muscular control: "Sandy flexes his brow characteristically" (Scott Turow).
4. To exhibit or show off the strength of: "They had spent six years since the lightning Six Day War flexing their invincibility" (Howard Kaplan).
v.intr.
To bend: "His hands flexed nervously as he spoke" (Mary McCarthy).
n.
1. Chiefly British Flexible insulated electric cord.
2. The act or an instance of flexing; a bending.
3. Flexibility: a schedule with a lot of flex.
Idiom:
flex (one's) muscles Informal
To exhibit or show off one's strength.
[Latin flectere, flex-, to bend.]
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.

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