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certain

/ˈsɜːrtn/
adjective★Intermediate— definite or sure
general

having no doubt; sure

She is certain of her success.

She is confident and sure that she will succeed.

💡

Often used to express strong confidence or assurance.

general

a specific but unspecified person or thing

A certain someone left a gift at my door.

An unspecified person left a gift at my door.

💡

Used to refer to someone or something without naming them directly.

Collocations

certain ofconfident aboutcertainlydefinitelyfor certaindefinitely or surely

Synonyms

sureconfidentdefinitepositive

Antonyms

uncertaindoubtfulunsure

Related Phrases

for certainphrase
definitely or surely
be certain ofphrase
to be confident about something

💡Pro Tip

Usage Tip

Use 'certain' to express strong confidence or to refer to an unspecified person or thing.

⚡Gold Rule

Grammar Rule

'Certain' can function as both an adjective and a determiner, but its meaning changes based on context.

📖Word Origin

From Old French 'certain', from Latin 'certus', meaning 'determined, resolved, sure'.

📝Usage Notes

Can be used as an adjective to describe a state of confidence or as a determiner to refer to an unspecified person or thing.

Word Breakdown

cert
sure, determined
root
+
-ain
belonging to
suffix
English Dictionary

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