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com·pound 1 (kŏm-pound, kəm-, kŏmpound)
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v. com·pound·ed, com·pound·ing, com·pounds
v.tr.
1. To combine so as to form a whole; mix: Tin was often compounded with lead to make pewter.
2. To produce or create by combining two or more ingredients or parts; compose or make up: pharmacists compounding prescriptions.
3. To settle (a debt, for example) by agreeing on an amount less than the claim; adjust.
4. To compute (interest) on the principal and accrued interest.
5.
a. To add to or intensify so as to make worse: "The university authorities ... compounded their crime in dismissing [the professor] by denying that their action ... reflected any abridgment of academic freedom" (John Kenneth Galbraith).
b. To make worse by being an additional or intensifying factor: High winds compounded the difficulties of the firefighters.
v.intr.
1. To combine in or form a compound.
2. To come to terms; agree.
adj. (kŏmpound, kŏm-pound, kəm-)
1. Consisting of two or more substances, ingredients, elements, or parts.
2. Botany Composed of more than one part: a compound pistil.
n. (kŏmpound)
1. A combination of two or more elements or parts.
2. Linguistics A word that consists either of two or more elements that are independent words, such as loudspeaker, self-portrait, or high school, or of specially modified combining forms of words, such as Greek philosophia, from philo-, "loving," and sophia, "wisdom."
3. Chemistry A pure, macroscopically homogeneous substance consisting of atoms or ions of two or more different elements in definite proportions that cannot be separated by physical means. A compound usually has properties unlike those of its constituent elements.

[Alteration of Middle English compounen, from Old French componre, compondre, to put together, from Latin compōnere; see COMPONENT.]

com·pounda·ble adj.
com·pounder n.

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
 
com·pound 2 (kŏmpound)
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n.
1. A building or buildings, especially a residence or group of residences, set off and enclosed by a barrier.
2. An enclosed area used for confining prisoners of war.

[Alteration (influenced by COMPOUND1) of Malay kampung, village, ward or quarter of a town, perhaps of Austroasiatic origin; compare Old Khmer kave, enclosing wall, rampart, nominalization (with nominalizing infix -ən-) of khve, to encircle, enclose : k-, intensive prefix + ve, to go around, enclose (akin to Mon wa, enclosure, and Koho (Austroasiatic language of southern Vietnam) waŋ, cattle yard).]

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. 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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