noun

1. the part of a plant, usually below the ground, that lacks nodes, shoots, and leaves, holds the plant in position, draws water and nourishment from the soil, and stores food
2. loosely any underground part of a plant, as a rhizome
3. the attached or embedded part of a bodily structure, as of the teeth, hair, nails, or tongue
4. the source, origin, or cause of an action, quality, condition, etc.
5. a person or family that has many descendants; ancestor
6. the close ties one has with some place or people as through birth, upbringing, long and sympathetic association, etc.
7. a lower or supporting part; base
8. an essential or basic part; core the root of the matter
9. Math.
   1. a quantity that, multiplied by itself a specified number of times, produces a given quantity 4 is the square root (4 × 4) of 16 and the cube root (4 × 4 × 4) of 64
   2. a number that, when substituted for the unknown quantity in an equation, will satisfy the equation
10. Music the basic tone of a chord, on which the chord is constructed; often, the fundamental
11. Linguis. the fundamental element of a word or form, exclusive of all affixes and inflectional phonetic changes

Etymology: ME rote < Late OE < ON rot, akin to OE wyrt, Ger wurzel < IE base *wrād-, twig, root > Gr rhiza, L radix, root, ramus, branch

intransitive verb

1. to begin to grow by putting out roots
2. to become fixed, settled, etc.

transitive verb

1. to fix the roots of in the ground
2. to establish; settle

transitive verb

Etymology: formerly also wrote, rout < ME wroten < OE wrotan, to root up < wrot, snout < IE base *wer-, to tear up > L rostrum, beak

intransitive verb

1. to dig in the ground, as with the snout
2. to search about; rummage to root through the litter
3. Informal to work hard; drudge to root for a living
4. ☆ Informal: usually with for
   1. to encourage a contestant or team by applauding and cheering
   2. to lend moral support to one seeking success, recovery, etc.