certain
- 1Marking out particular but unspecified people or things from a larger group.
Certain medications should not be mixed with alcohol.
The rule applies only under certain conditions.
UsageUsually with a plural or uncountable noun and no article: certain people, certain information; with a singular countable noun, use a certain.
Similarsome
- 2Fully confident in your own mind, with no doubt that something is true.
The witness seemed certain about every detail of the night.
Are you certain you turned off the stove?
UsageFollowed by of, about or a that clause: certain of my decision, certain that I locked it.
- 3Used to refer to a particular person or thing without naming or describing it, sometimes because the listener is expected to know who or what is meant.
Late one evening, a certain traveler arrived at the inn asking for a room and a hot meal.
The old farmhouse has a certain charm that the newer houses on the road lack.
UsageFollows a and comes before its noun: a certain traveler, a certain charm.
Note
Two jobs fall to this use. It brings a person or place into a story without naming it, like a certain city in the King James Bible of 1611. It also stands before a quality that is real but hard to pin down: Macaulay, writing in 1856, finds a certain natural grace in all his subject wrote.
- 4Fixed, regular, or set: determinate in amount, time, or arrangement.
To be negotiable, a promissory note must promise to pay a sum certain, not an amount left to be worked out later.
Under the contract, the buyer must pay a sum certain rather than a share of the profits.
UsageIn legal writing it can follow its noun: a sum certain.
Similarfixed, set, regular, determinate
Note
Here the word means fixed or set, not merely particular. When the King James Bible of 1611 has the people gather a certain rate every day, it means a fixed daily amount. At certain intervals can carry this meaning, but it is easily heard as the "particular but unnamed" use. If regularity matters, fixed or regular says it without ambiguity.
Checked 5 Nov 2026 · 3 facts
- The King James Bible was first published in 1611. en.wikipedia.org
- Exodus 16:4 in the 1611 King James Bible contains the instruction to gather 'a certain rate every day', with original spelling 'a certaine rate euery day'. en.wiktionary.org
- The Exodus example illustrates the sense 'fixed; regular; determinate'. en.wiktionary.org
- 5Bound to happen no matter what; inevitable and assured.
The soldiers marched toward what seemed like certain death.
With the lead this large, victory was certain by halftime.
Usagecertain to + verb (Spain is certain to win), or before a noun for an outcome no one escapes: certain death.
Similarinevitable, sure, assured, guaranteed, unavoidable
Note
Dryden's Aureng-zebe (1675) sets it against its opposite: virtue leads us through certain danger to uncertain praise. The danger is sure to come, while the reward may never arrive.
- 6Known to be true beyond doubt, so that no one can reasonably deny it.
One thing is certain: the letter was written by someone who knew the family well.
The evidence makes it certain that the fire began in the kitchen.
UsageOften one thing is certain, or it is certain that + clause.
Similarclear, definite, indisputable, undeniable, unquestionable
Oppositeuncertain, doubtful, questionable
Less common meanings
- 7Some particular but unnamed members of a larger group.
Certain of the guests left before the speeches even began.
Certain of his early poems were never published in his lifetime.
UsageUsually followed by of + a plural: certain of the guests; some of is the plain everyday choice.
Similarsome
- 8Used before a person's name to introduce someone the listener is not expected to know, or playfully before the name of someone very well known.
The estate had been bought by a certain Mr. Harrow, of whom the villagers knew nothing.
Our office received a complaint from a certain Diane Foster last week.
Usagea certain + a name, for someone the reader does not know: a certain Mr. Harrow; before a famous name it is playful.
- 9Never failing; sure to work or take effect every time.
The hunter's aim with the bow was certain, even in failing light.
The old herbalist sold his tonic as a certain remedy for every ache, though it rarely helped anyone.
Similarsure, unerring, unfailing, reliable
Oppositeunreliable
- 10Firmly resolved or determined upon a course of action.
Note
Milton still uses it in 1667. In Paradise Lost, certain to undergo like doom means resolved to share the same fate, not sure that the fate will come. The phrase looks exactly like the modern certain to (certain to reach the finals), so older verse is easy to misread here. This sense keeps the "resolved" of Latin certus. Today, write determined or resolved instead.
Checked 5 Nov 2026 · 5 facts
- John Milton's Paradise Lost was first published in 1667. en.wikipedia.org
- The first publication year was 1667. en.wikipedia.org
- Paradise Lost contains the quoted wording, spoken by Adam to Eve. gutenberg.org
- Certain in this passage means determined or resolved to share Eve's fate. en.wiktionary.org
- Certain derives ultimately from Latin certus, whose meanings include resolved. en.wiktionary.org
Showing meanings only.
Practice
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Origin
It came through Middle English and Old French from an unrecorded Vulgar Latin form *certānus, based on Latin certus ("fixed, resolved, certain"), related to cernere ("to separate, perceive, decide"). It replaced the native English words wis and iwis.
Checked 5 Nov 2026 · 5 facts
- Certain came through Middle English and Old French. en.wiktionary.org
- The reconstructed Vulgar Latin form *certānus was based on Latin certus, meaning fixed, resolved, certain. en.wiktionary.org
- Latin certus is related to cernere. en.wiktionary.org
- Cernere means to separate, perceive, decide. en.wiktionary.org
- Certain displaced the native English words wis and iwis. en.wiktionary.org