# certain

Pronunciation: say "SUR-tuhn" US /ˈsɝtən/, UK /ˈsɜːtən/

## Determiner

1. Marking out particular but unspecified people or things from a larger group.
   - Simple: Used for some particular people or things without saying exactly which ones.
   - _Certain medications should not be mixed with alcohol._
   - _The rule applies only under certain conditions._

## Adjective

2. Fully confident in your own mind, with no doubt that something is true.
   - Simple: Completely sure in your mind that something is true.
   - _The witness seemed certain about every detail of the night._
   - _Are you certain you turned off the stove?_
3. Used 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.
   - Simple: Used to talk about one particular person or thing without saying exactly who or which it is.
   - _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._
4. Fixed, regular, or set: determinate in amount, time, or arrangement.
   - Simple: Fixed or set in a way that does not change, such as an exact amount.
   - _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._
5. Bound to happen no matter what; inevitable and assured.
   - Simple: Sure to happen, with no way to stop or avoid it.
   - _The soldiers marched toward what seemed like certain death._
   - _With the lead this large, victory was certain by halftime._
6. Known to be true beyond doubt, so that no one can reasonably deny it.
   - Simple: True and proven, so that no one can doubt 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._
8. Used 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.
   - Simple: Used before a name to mean 'a person called this', or as a joke with the name of someone famous.
   - _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._
9. Never failing; sure to work or take effect every time.
   - Simple: Always working as expected and never failing.
   - _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._

## Pronoun

7. Some particular but unnamed members of a larger group.
   - Simple: Some particular members of a group, not named.
   - _Certain of the guests left before the speeches even began._
   - _Certain of his early poems were never published in his lifetime._

## Adjective

10. Firmly resolved or determined upon a course of action. *(obsolete)*
   - Simple: Firmly decided and set on doing something.

## 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.

Source: DictionaryAI, https://dictionaryai.com/define/certain (written from Wiktionary data, CC BY-SA 4.0: https://creativecommons.org/licenses/by-sa/4.0/).