root
root — noun
- rootsingular
- rootsplural
1. the portion of a plant found beneath the earth's surface, which draws moisture a
the portion of a plant found beneath the earth's surface, which draws moisture and nutrients from the surrounding soil while keeping the plant upright and stable.
The oak tree's roots spread wide under the garden soil.
collocation: spread wide / deep roots
Ramón carefully dug around the carrot to avoid cutting the root.
concrete action: dig around to avoid cutting
These plants have shallow roots, so they need watering every day.
adjective + root: shallow / deep roots
When a tree falls in a storm, the roots are often pulled out of the ground.
- deep roots
- shallow roots
- root system
- pull up by the roots
- root ball
Usage Note
Often appears in the plural form roots when referring to the whole underground system of a plant.
2. the main reason that a bad situation or problem exists; the thing from which som
the main reason that a bad situation or problem exists; the thing from which something unpleasant grows.
Lack of sleep is often the root of many health problems.
the root of + problem / issue
The police are trying to get to the root of the corruption scandal.
get to the root of something
Christopher believes that poverty is at the root of most social conflicts.
at the root of something
The committee traced the root of the financial crisis back to poor lending practices.
- root cause
- the root of the problem
- get to the root of
- at the root of
Usage Note
Common in fixed phrases like 'root cause', 'the root of the problem', and 'get to the root of something'. Unlike sense 3 (ORIGINS), this sense has a negative connotation — the thing being described is undesirable.
Common Mistakes
3. a person's family, cultural, or geographic background; the place or community th
a person's family, cultural, or geographic background; the place or community that a person or thing comes from originally.
Padma decided to return to her roots in southern India after twenty years abroad.
return to one's roots
The music festival celebrates the Celtic roots of the region's folk traditions.
cultural / ethnic roots
Yael's family has deep roots in the farming community of the valley.
deep roots in a place
Many traditional dishes have their roots in home cooking rather than restaurant kitchens.
have its roots in something
- return to one's roots
- have roots in
- deep roots
- cultural roots
- family roots
- heritage
traditions and values passed down; broader and more abstract than roots
- background
the kind of family and experience someone has; less emotional
- ancestry
specifically about family lines going back generations
Usage Note
Almost always used in the plural (roots). The emphasis is on connection to a place, culture, or tradition — different from sense 2 (ROOT CAUSE), which focuses on negative causation.
4. the section of a tooth, hair strand, or fingernail that sits beneath the skin su
the section of a tooth, hair strand, or fingernail that sits beneath the skin surface or gum, holding it firmly in place.
The dentist said the infection had reached the root of my molar.
tooth root / root of a tooth
Zuri noticed a grey hair growing from the root near her temple.
hair root / grows from the root
Damage to the nail root can make the fingernail grow back with an odd shape.
nail root
The dentist used an X-ray to check whether the root of the cracked tooth was still healthy.
- tooth root
- hair root
- nail root
- root of the tooth
- root canal
Usage Note
Often used in compound nouns: tooth root, hair root, nail root. The root is the living part that produces new growth (for hair/nails) or anchors the structure (for teeth).
5. the smallest meaningful unit in a language, to which prefixes and suffixes may b
the smallest meaningful unit in a language, to which prefixes and suffixes may be attached to build related vocabulary.
The Latin root 'scrib' means 'to write' and appears in 'describe' and 'inscribe'.
Latin / Greek root + examples
Quan looked up the root of 'photograph' and found it comes from Greek words for 'light' and 'writing'.
root of a word / comes from
Takeshi recognised the Greek root 'bio' in 'biodegradable' and guessed it meant 'life'.
recognise a Greek root in an unfamiliar word
The word 'biology' has the Greek root 'bios', which means 'life'.
- Latin root
- Greek root
- word root
- root meaning
- common root
- affix
a prefix or suffix added to a root
Usage Note
In linguistics, a root differs from a stem or base — the root is the smallest meaningful part. But in everyday learning, 'root' is used more loosely to mean any core word from which related words are formed.
6. a value that makes a mathematical equation true when it is put in place of the u
a value that makes a mathematical equation true when it is put in place of the unknown variable.
The quadratic equation x² − 9 = 0 has two roots, which are the numbers 3 and −3.
has two roots (equation solving)
Sumin solved the quadratic and found the roots were real numbers.
real roots / complex roots
For her algebra test, Anong solved x³ − 8 = 0 and found that 2 was a real root.
solve a cubic equation to find a real root
Noa solved for the roots of the polynomial and found both were positive integers.
- real root
- complex root
- square root
- cube root
- root of an equation
Usage Note
Distinct from sense 7 (SQUARE ROOT). In this sense, 'root' means any solution to an equation — not limited to square roots. For example, the roots of x − 5 = 0 is just 5.
7. a value that serves as a factor in repeated self-multiplication a set count of t
a value that serves as a factor in repeated self-multiplication a set count of times to arrive at a particular result — the square root of 16 is 4, since 4 × 4 = 16.
The square root of 64 is 8, because multiplying 8 by itself gives the total of 64.
square root of [number]
Élise used a calculator to find the cube root of 27.
cube root / square root
For her math homework, Ayana calculated the square root of 144 and got 12.
calculate the square root of a specific number
The cube root of 125 is 5, because multiplying 5 by itself three times gives 125.
- square root
- cube root
- principal root
- nth root
Usage Note
Distinguish from sense 6 (EQUATION SOLUTION). Sense 7 is specifically about roots of numbers (e.g. square root, cube root), while sense 6 is about roots of equations. In math notation, a square root is shown with the √ symbol.
8. the pitch at the bottom of a chord, which determines the chord's name and its ov
the pitch at the bottom of a chord, which determines the chord's name and its overall harmonic quality.
In a C major chord, the note C is the root of the chord.
root of the chord
Rania learned to identify the root note by listening to the lowest pitch in a chord.
root note
Ezra played the C major chord on his guitar, then moved the root to E and heard a different chord.
move the root of a chord on guitar
In a G major chord, the note G serves as the root and the chord is built up from there.
- root note
- root of the chord
- root position
- chord root
- tonic
often confused; tonic is the first note of a scale, while root is the base of a chord
- fundamental
in acoustics, the lowest frequency of a sound; related but not identical
Usage Note
Used mainly in music theory. In a chord, the other notes (third, fifth, seventh) are described in relation to the root.
root — verb
- rootpresent simple I / you / we / they
- roots3rd person singular
- rooting-ing form
- rootedpast simple
1. to search for something by moving things around or turning them over, often in a
to search for something by moving things around or turning them over, often in a rough or careless way.
Noa rooted through the drawer looking for a pair of scissors.
root through + noun phrase
The pig was rooting around in the mud with its snout.
root around
Lotte rooted in her backpack for the train ticket while the queue moved forward.
Lotte rooted around in the toolbox until she found the right screwdriver.
- root through
- root around
- root in
- root about
Grammar Patterns
root + through/around + noun phrase
Usage Note
Almost always used with a particle like through, around, or in. The object being searched through is usually a messy container or area (drawer, bag, pile, soil).
Common Mistakes
2. of a plant or cutting: to send out roots and start establishing itself in soil o
of a plant or cutting: to send out roots and start establishing itself in soil or another growing material.
The rose cuttings took about three weeks to root in the potting mix.
to root in [growing medium]
Eve placed the stem in water until it rooted, then planted it in a pot.
Mrs. Chen placed her jasmine cuttings in a jar of water on the windowsill, hoping they would root.
root cuttings in water
The gardener showed us how to root lavender cuttings in small pots of sand.
root + noun (cutting) + in + medium
- root easily
- root from cuttings
- root in soil
- root in water
Usage Note
This verb is often used in gardening contexts. The related phrasal verb 'take root' is more common in everyday speech for the same idea. The transitive form (root a cutting) is also used by gardeners.
Word family
Synonym discussion
Sense: noun/1
All four words refer to underground plant parts, but they differ in structure and usage. Root is the general term for any part of a plant that grows downward into the soil, absorbing water and nutrients — it is the everyday word used by gardeners and non-experts alike. A tuber is a thick, fleshy underground stem (like a potato) that stores food; it is not technically a root, though many learners call it one. A rhizome is a horizontal underground stem that spreads sideways and sends out roots and shoots from its nodes — ginger is a common example. A bulb is a rounded storage organ with layers of fleshy leaves (like an onion or tulip). In practice: 'The carrot is a root vegetable, while the potato is a tuber, not a root.'
Common collocations
Etymology
The word root comes from Old English rōt, which was borrowed from Old Norse rót, meaning 'underground part of a plant.' This Germanic root word goes back to the Indo-European base *wrd-, also meaning 'root' or 'branch.' The same ancient source gave rise to Latin radix (root), which later gave English words like 'radish' and 'radical.' The figurative meanings — such as 'origin' or 'cause' — appeared in English as early as the 12th century, extending the physical sense of something that something else grows from.
First known use
12th century
12th century, in the meaning defined at sense 1b Verb (1)