root¹ (rūt, rʊt)
n.

1. The usually underground portion of a plant that lacks buds, leaves, or nodes and serves as support, draws minerals and water from the surrounding soil, and sometimes stores food.
2. Any of various other underground plant parts, especially an underground stem such as a rhizome, corm, or tuber.
3. 1. The embedded part of an organ or structure such as a hair, tooth, or nerve, that serves as a base or support.
   2. A base or support: We snipped the wires at the roots.
4. An essential part or element; the basic core: I finally got to the root of the problem.
5. A primary source; an origin. See synonyms at origin.
6. A progenitor or ancestor from which a person or family is descended.
7. 1. The condition of being settled and of belonging to a particular place or society. Often used in the plural: Our roots in this town go back a long way.
   2. roots The state of having or establishing an indigenous relationship with or a personal affinity for a particular culture, society, or environment: music with unmistakable African roots.
8. Linguistics.
   1. The element that carries the main component of meaning in a word and provides the basis from which a word is derived by adding affixes or inflectional endings or by phonetic change.
   2. Such an element reconstructed for a protolanguage. Also called radical.
9. Mathematics.
   1. A number that when multiplied by itself an indicated number of times forms a product equal to a specified number. For example, a fourth root of 4 is √2. Also called nth root.
   2. A number that reduces a polynomial equation in one variable to an identity when it is substituted for the variable.
   3. A number at which a polynomial has the value zero.
10. Music.
    1. The note from which a chord is built.
    2. Such a note occurring as the lowest note of a triad or other chord.

v., root·ed, root·ing, roots.

v.intr.

1. To grow roots or a root.
2. To become firmly established, settled, or entrenched.
3. To come into existence; originate.

v.tr.

1. To cause to put out roots and grow.
2. To implant by or as if by the roots.
3. To furnish a primary source or origin to.
4. To remove by or as if by the roots. Often used with up or out: "declared that waste and fraud will be vigorously rooted out of Government" (New York Times).

idiom:

root and branch

1. Utterly; completely: The organization has been transformed root and branch by its new leaders.

[Middle English rot, from Old English rōt, from Old Norse.]

rooter root'er n.

root² (rūt, rʊt)

v., root·ed, root·ing, roots.

v.tr.
To dig with or as if with the snout or nose: Even a blind hog can root up an acorn.

v.intr.

1. To dig in the earth with or as if with the snout or nose.
2. To rummage for something: rooted around for a pencil in his cluttered office.

[Middle English wroten, from Old English wrōtan.]

rooter root'er n.

root³ (rūt, rʊt)
intr.v., root·ed, root·ing, roots.

1. To give audible encouragement or applause to a contestant or team; cheer. See synonyms at applaud.
2. To lend support to someone or something.

[Possibly alteration of ROUT³.]

rooter root'er n.

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The American Heritage® Dictionary of the English Language, Fourth Edition Copyright © 2007, 2000 by Houghton Mifflin Company. Updated in 2009. Published by Houghton Mifflin Company. All rights reserved.

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