tain
Latinhold, keep
About This Root
The root tain comes from Latin tenēre, "to hold, to keep, to grasp." Picture a hand closing around something and not letting go — that single gesture is the heart of the entire family. Whatever a tain word is doing, it is keeping a grip on something.
The magic happens when prefixes tell you how or in what direction the holding goes:
- con- (together) + tain → contain: hold things together inside one space. A box contains; a country contains its borders.
- re- (back) + tain → retain: hold something back, keep it from leaving. You retain water, retain staff, retain the right.
- ob- (toward, onto) + tain → obtain: get a hold of something through effort — reach out and grasp it.
- sus- (a form of sub-, from below) + tain → sustain: hold something up from underneath so it keeps going.
- de- (away, aside) + tain → detain: hold someone back/aside, stop them from moving on.
- abs- (away) + tain → abstain: hold yourself away from something.
- per- (through, thoroughly) + tain → pertain: hold all the way through to a matter — to be connected to it.
Two members hide their prefix. maintain comes from Old French maintenir, from Latin manū tenēre — literally "to hold in the hand" (manus = hand). So the main- in maintain is not "main/chief" at all; it is the worn-down ghost of manus, the hand that keeps things in good order. entertain comes from inter- (between) + tenēre: "to hold between/among" — originally to keep someone in a certain state of mind, to hold their attention. Holding an audience's attention is exactly what entertainers still do.
On the surface the root changes shape. After a prefix and before a vowel it usually appears as tain (contain, retain, obtain). Inside longer words and in older formations it flattens to ten (continent, continuous, abstinent) or tin (continue, continuity), and the past-participle form tentum gives tent (content, contented, discontent). They all trace back to the same closed hand.
The pattern to remember: the root tain/ten/tin/tent is always "hold/keep," and the prefix tells you which way the holding points — together, back, toward, from below, away.
Think of a closed hand holding tight — tenēre means "to hold." A container holds things together (con-), to retain is to hold back (re-), to obtain is to get a hold of something. Even maintain is the same root hiding a hand: main- is Latin manus, so to maintain is literally to keep something "in hand."
Core Words Deep Dive
The few words from this family worth telling in full — one by one.
Two completely different words spelled the same, split by stress. CON-tent (noun, stress on first syllable) = what is held inside: the content of a box, video content. con-TENT (adjective/verb, stress on second syllable) = held together and at rest, hence satisfied — your desires are 'contained,' nothing spills over wanting more. Both come from con- (together) + tenēre (hold): one holds material inside, the other holds your wishes in check.
The hidden hand. main- is not English 'main'; it is Latin manus (hand) worn down through Old French maintenir, from manū tenēre = 'to hold in the hand.' To maintain a road, a position, or a claim is to keep your hand on it so it doesn't fall apart. The 'assert/claim' sense (maintain that...) is the same image: you keep holding to your statement even under pressure.
con- (together) + tin (hold) = to hold things together across time, with no gap. The whole continu- family branches from this: continuous (no break at all), continual (holding on but with repeated pauses), continuity (the unbroken thread), continent (originally 'holding together' — a landmass held together as one piece).
sus- (a form of sub-, 'from below') + tain (hold) = to hold up from underneath so something keeps going. Picture a hand under a sagging beam. From that physical image come all its senses: sustain life (keep it going), sustain growth (keep it up over time), and even sustain an injury — the odd one out, where you 'undergo/bear' the blow rather than support it.
inter- (between/among) + tenēre (hold) = to 'hold between,' originally to keep someone in a state of mind. Three senses survive: hold an audience's attention (amuse), hold guests (host them), and hold an idea in mind (entertain a thought/possibility). All three are about keeping something — attention, people, or an idea — in your grip.
Related Roots
Associated Words · 87
abstain
To refrain from something; to choose not to vote
abstainer
A person who refrains from something, especially alcohol
abstention
The act of refraining; a decision not to vote
abstinence
The practice of refraining from food, alcohol, or other desires
abstinent
Refraining from indulging in food, drink, or other appetites
attain
To achieve or reach a goal through effort
attainable
Able to be achieved or obtained
attainment
The act of achieving a goal; something accomplished through effort
contain
To hold inside
container
An object used to hold things; a large metal shipping box
containment
The act of keeping something harmful from spreading; a policy of limiting hostile expansion
content
Subject matter or material (n.); satisfied (adj.); to satisfy (v.)
contented
Feeling satisfaction and ease with one's situation
contentment
A feeling of peaceful happiness and satisfaction
contents
Things held inside a container; a list of chapters in a book
continence
Self-restraint, especially in sexual matters; voluntary control over bodily functions
continent
One of the seven main landmasses of the Earth; exercising self-restraint
continental
Of or relating to a continent; characteristic of mainland Europe
continual
Happening repeatedly and frequently; seemingly unending
continually
Repeatedly and frequently; without apparent interruption
continuation
The act of continuing without interruption; something that extends or carries on
continue
To proceed with (doing an activity); to prolong (an activity); An option allowing a gamer to resume play after game over, when all lives have been lost
continued
Prolonged without interruption; ongoing
continuity
Uninterrupted connection or consistency over time
continuous
Going on without stopping or interruption
continuously
Without stopping or pausing
continuum
A continuous series where no part is sharply distinct from adjacent parts
countenance
A person's facial expression; to tolerate or approve of something
detain
To hold someone in custody; to delay or hold back
detainment
The state of being held in custody; detention
discontent
Dissatisfaction with one's situation; feeling or causing unhappiness
discontinuation
The act of stopping or ending something
discontinue
To permanently stop producing or doing something
discontinued
No longer produced or available
discontinuity
A break or gap in continuity
discontinuous
Not continuous; having breaks or interruptions
entertain
To amuse an audience; to host guests; to consider an idea
entertainer
A person who performs for or amuses an audience
entertaining
Amusing and enjoyable; holding one's attention pleasantly
entertainingly
In an amusing and enjoyable manner
entertainment
Activities or performances designed to amuse or interest people
impertinence
Rude or disrespectful behavior; irrelevance
impertinent
Rude and disrespectful; not relevant
lieutenant
A junior military officer rank; a deputy or assistant to a superior
life-sustaining
Necessary for keeping someone alive
maintain
to keep up or preserve; to assert as true; to repair
maintainable
Capable of being maintained
maintained
Kept in good condition or a particular state
maintainer
A person who maintains or upholds something
maintenance
Work done to keep something in good condition; financial support after divorce
obtain
To get or acquire something through effort
obtainable
Able to be acquired or achieved
pertain
To relate or be relevant to something; to belong to
pertaining
Relating or belonging to a particular matter
pertinence
The quality of being directly relevant
pertinent
Directly relevant to the matter at hand
pertinently
In a directly relevant manner
retain
To keep or continue to have something
retained
Kept in one's possession; not given up
retainer
A fee paid to secure services; a loyal servant; a dental device
retention
The act of keeping something; the ability to remember information
retentive
Having the ability to retain or remember things well
self-sustaining
Able to continue or maintain without external support
sustain
To maintain or keep going; to provide nourishment or support
sustainability
The ability to maintain something without depleting resources or harming the environment
sustainable
Able to be maintained long-term without harming the environment
sustained
Continuing at the same level for a long time
sustainer
A person or thing that sustains; a regular donor
sustainment
The act of sustaining or maintaining something
sustenance
Food or nourishment needed to sustain life
tenable
Able to be logically defended or justified; well-founded
tenacious
Persistent, determined, and unwilling to give up
tenaciously
In a determined, persistent manner
tenacity
Persistent determination; firmness of purpose
tenancy
The right to occupy property by paying rent; the period of such occupation
tenant
A person who pays rent to use property owned by another
tenement
A run-down apartment building rented to multiple tenants in a poor area
tenet
A core belief or principle held as true by a person or organization
tenor
The highest natural adult male singing voice; the general meaning or drift of something
tenure
The period of holding a position; a permanent academic post
unattainable
Impossible to achieve or obtain
unmaintained
Not kept in good condition or regularly serviced
unobtainable
Impossible to get or acquire
unsustainability
The condition of being unable to be maintained over time
unsustainable
Unable to be maintained or continued over time
untenable
Impossible to defend or justify as a position
well-maintained
Kept in good condition through regular care