root-n; 6 Senses

Sense Number 1: BOTANY -- the usually underground organ of a plant that lacks buds or leaves or nodes, which absorbs water and mineral salts; usually it anchors the plant to the ground.

Commentary: ROOT[+plant_life]

The roots of the ivy plant tunnelled into the house, destroying the bricks and foundation.
The root of the iris plant is used in perfumery.
Janists do not eat the roots of any plant.

WordNet 3.0 Sense Numbers: 1

Sense Number 2: the place where something originates, begins, or springs into being. If a human familial relation is implied or expressed, please tag it as sense #5.

Commentary: ROOT[+event][+location]

We speak of Marx and Engels, communism's Russian root.
The root of her grief is the loss of her beloved Father.
She wanted to get back to her roots.
Money is the root of all evil.

WordNet 3.0 Sense Numbers: 2

Sense Number 3: LINGUISTICS -- the form of a word after all affixes are removed; a simple form inferred as the common basis from which related words in several languages can be derived by linguistic processes.

Commentary: ROOT[+non-human][+non-animate][+linguistic_terminology]

Thematic vowels are part of the root.
The roots of words are often determined by looking at how words are similar across many daughter languages.
The root of the past-tense verb 'went' is 'go'.

WordNet 3.0 Sense Numbers: 3, 7

Sense Number 4: a number that, when multiplied by itself some number of times, equals a given number, or the set of values that give a true statement when substituted into an equation.

Commentary: ROOT[+number][+non-human][+non-animate]

4 is the square root of 16.
The root of the equation is x equals 2.

WordNet 3.0 Sense Numbers: 4, 5

Sense Number 5: someone from whom you are descended but usually more remote than a grandparent. Note that this sense is different from #2, in that the root person is often specified or otherwise implied.

Commentary: ROOT[+relationship][+family_tie]

My family's root is the matriarch of the Cullen clan.
Her family's roots are in French royalty.
Discovering her family's roots meant looking for records from Staten Island.

WordNet 3.0 Sense Numbers: 6

Sense Number 6: the part of a tooth that is embedded in the jaw and serves as support.

Commentary: ROOT[+dental_terminology][+animate]

The tooth was so rotted that the root died, and the dentist had to do a root canal.
A curled part of the nerve remained in the root and so the whole thing had to be removed.

WordNet 3.0 Sense Numbers: 8