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root 1 (rt, rt)
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n.
1.
a. 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.
b. Any of various other underground plant parts, especially an underground stem such as a rhizome, corm, or tuber.
2.
a. The embedded part of an organ or structure such as a hair, tooth, or nerve, that serves as a base or support.
b. The bottom or supporting part of something: We snipped the wires at the roots.
3. The essential part or element; the basic core: I finally got to the root of the problem.
4. A primary source; an origin. See Synonyms at origin.
5. A progenitor or ancestor from which a person or family is descended.
6.
a. often roots The condition of being settled and of belonging to a particular place or society: Our roots in this town go back a long way.
b. 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.
7. Linguistics
a. 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.
b. Such an element reconstructed for a protolanguage. Also called radical.
8. Mathematics
a. 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.
b. A number that reduces a polynomial equation in one variable to an identity when it is substituted for the variable.
c. A number at which a polynomial has the value zero.
9. Music
a. The note from which a chord is built.
b. 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: Carrot tops will root in water.
2. To become firmly established or settled: The idea of tolerance has rooted in our culture.
v.tr.
1. To plant and fix the roots of (a plant) in soil or the ground.
2. To establish or settle firmly: Our love of the ocean has rooted us here.
3. To be the source or origin of: "Much of [the team's] success was rooted in the bullpen" (Dan Shaughnessy).
4.
a. To dig or pull out by the roots. Often used with up or out: We rooted out the tree stumps with a tractor.
b. To remove or get rid of. Often used with out: "declared that waste and fraud will be vigorously rooted out of Government" (New York Times).
Idiom:
root and branch
Utterly; completely: The organization has been transformed root and branch by its new leaders.

[Middle English rot, from Old English rōt, from Old Norse; see wrād- in the Appendix of Indo-European roots.]

rooter n.

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2017 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
 
root 2 (rt, rt)
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v. root·ed, root·ing, roots
v.tr.
1. To turn up by digging with the snout or nose: hogs that rooted up acorns.
2. To cause to appear or be known. Used with out: an investigation that rooted out the source of the problem.
v.intr.
1. To turn over the earth with the snout or nose.
2. To search or rummage for something: rooted around for a pencil in his cluttered office.

[Middle English wroten, from Old English wrōtan.]

rooter n.

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2017 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
 
root 3 (rt, rt)
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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 give moral support to someone; hope for a favorable outcome for someone: We'll be rooting for you when you take the exam.

[Possibly alteration of ROUT3.]

rooter n.

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2017 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
 
Root (rt), Elihu 1845-1937.
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American lawyer and public official who served as US secretary of war (1899-1904), secretary of state (1905-1909), and senator from New York (1909-1915). He won the 1912 Nobel Peace Prize for his work in international law.

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2017 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
 

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