A number that when multiplied by itself some number of times equals a given number.
Of an equation, a value that satisfies the equality. For example, x = 0 and x = 5 are roots of the equation x2 -5x = 0.

Elihu 1845-1937 American lawyer and statesman.

ETYM Icel. rôt (for vrôt); akin to Eng. wort, and perhaps to root to turn up the earth. Related to Wort.
(Homonym: route).
The part of a tooth that is embedded in the jaw and serves as support; SYN. tooth root.

(Homonym: route).
1. To take root; begin to grow; of plants.
2. To have an origin or base.
3. To noisily applaud or encourage a contestant or team; cheer.
4. To wish the success of or lend support to someone or something.

(Linguistics) The form of a word after all affixes are removed; SYN. root word, base, stem, theme, radical.
In language, the basic element from which a word is derived. The root is a morpheme, a unit that cannot be subdivided. The Latin word dominus (“master”), for example, is a root from which many English words are derived, such as “dominate”, “dominion”, and “domino”.

In music, in a chord, the tonic note from which the other notes are derived. For example, in a chord consisting of any spacing or arrangement of the notes C–E–G, C is always the root. A chord is considered to be in “root position” when the root is the lowest voice or part, usually in the bass.

The usually underground portion of a plant that lacks buds or leaves or nodes; absorbs water and mineral salts; usually it anchors the plant to the ground.
The part of a plant that is usually underground, and whose primary functions are anchorage and the absorption of water and dissolved mineral salts. Roots usually grow downward and toward water (that is, they are positively geotropic and hydrotropic; see tropism). Plants such as epiphytic orchids, which grow above ground, produce aerial roots that absorb moisture from the atmosphere. Others, such as ivy, have climbing roots arising from the stems, which serve to attach the plant to trees and walls.
The absorptive area of roots is greatly increased by the numerous, slender root hairs formed near the tips. A calyptra, or root cap, protects the tip of the root from abrasion as it grows through the soil.
Symbiotic associations occur between the roots of certain plants, such as clover, and various bacteria that fix nitrogen from the air (see nitrogen fixation). Other modifications of roots include contractile roots, pneumatophores, taproots, and prop roots.

1. The superuser on UNIX/Linux platforms. The root user (or simply root) in UNIX corresponds to the Administrator account on Microsoft Windows plat-forms and is the all-powerful account with virtually complete control over the system. Because of its extraordinary rights and privileges, root should always be protected with strong passwords, and only trusted individuals should be granted access to this account. The power of the account also makes it a prime target for attackers, however. The “quest for root” is the “holy grail” of cracking since gaining control of this account allows attackers to defeat virtually every aspect of a UNIX system’s security, except any protection mechanisms
implemented using physical security on the premises,
such as lock-and-key access to a network attached storage (NAS) device or token-based smart card authentication. If an intruder is able to compromise root, the intruder also can erase all trail of the exploit by cleaning system logs and other auditing information, though there may be residual evidence that the audit log has been purged.
2. The main or uppermost level in a hierarchically organized set of information. The root is the point from which subsets branch in a logical sequence that moves from a broad focus to narrower perspectives. See also leaf, tree.