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re·duce (rĭ-ds, -dys)
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v. re·duced, re·duc·ing, re·duc·es
v.tr.
1. To bring down, as in extent, amount, or degree; diminish. See Synonyms at decrease.
2. To bring to a humbler, weaker, difficult, or forced state or condition; especially:
a. To gain control of; subject or conquer: "a design to reduce them under absolute despotism" (Declaration of Independence).
b. To subject to destruction: Enemy bombers reduced the city to rubble.
c. To bring to a specified undesirable state, as of weakness or helplessness: disease that reduced the patient to emaciation; teasing that reduced the child to tears.
d. To compel to desperate acts: The Depression reduced many to begging on street corners.
e. To lower in rank or grade; demote.
3. To thicken or intensify the flavor of (a sauce, for example) by slow boiling.
4. To lower the price of: The store has drastically reduced winter coats.
5. To decrease the viscosity of (paint, for example), as by adding a solvent.
6. To put in a simpler or more systematic form; simplify or codify: reduced her ideas to a collection of maxims.
7. To turn into powder; pulverize.
8. Chemistry
a. To decrease the valence of (an atom) by adding electrons.
b. To remove oxygen from (a compound).
c. To add hydrogen to (a compound).
d. To change to a metallic state by removing nonmetallic constituents; smelt.
9. Mathematics To simplify the form of (an expression, such as a fraction) without changing the value.
10. Medicine To restore (a fractured or displaced body part) to a normal condition or position.
11. Linguistics To pronounce (a stressed vowel) as the unstressed version of that vowel or as schwa.
v.intr.
1. To become diminished.
2. To lose weight, as by dieting.
3. Biology To undergo meiosis.

[Middle English reducen, to bring back, from Old French reducier, from Latin redūcere : re-, re- + dūcere, to lead; see deuk- in the Appendix of Indo-European roots.]

re·ducer n.
re·duci·bili·ty n.
re·duci·ble adj.
re·duci·bly adv.

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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