verb Uncommon

ascertain

a-suh-TAYN

Ascertain (verb) means to find out or establish something for certain, usually through checking or investigation. Example: “Investigators worked to ascertain the cause of the fire.”

verb

To find out or establish something for certain, usually through checking or investigation.

"Investigators worked to ascertain the cause of the fire."

"Please ascertain whether the shipment has arrived before calling the client."

How to Use Ascertain

Learner’s notes

In plain EnglishTo check and confirm a fact rather than just assume it.

When to use it

Fairly formal; "find out" or "check" is more natural in everyday speech.

Common pairings

ascertain the facts ascertain whether difficult to ascertain

Word Forms

ascertained past tense, ascertains singular

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Investigators worked to _____ the cause of the fire.

Etymology

From Old French acertener, "to make certain," ultimately from Latin certus ("certain, sure") — the same root as "certain."

Origin: Latin

Rhymes for ascertain

ain rain pain lain gain main vain fain bain Iain Jain Cain

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Frequently Asked Questions

What does “ascertain” mean?

The word “ascertain” means to find out or establish something for certain, usually through checking or investigation. In plain terms, to check and confirm a fact rather than just assume it.

How do you pronounce “ascertain”?

“Ascertain” is pronounced a-suh-TAYN (/ˌæsɚˈteɪn/ in IPA).

How do you use “ascertain” in a sentence?

Here is “ascertain” used in a sentence: “Investigators worked to ascertain the cause of the fire.”

What part of speech is “ascertain”?

“Ascertain” is a verb.

Where does the word “ascertain” come from?

The word “ascertain” comes from Latin. From Old French acertener, "to make certain," ultimately from Latin certus ("certain, sure") — the same root as "certain.".

Is “ascertain” a common word?

“Ascertain” is an uncommon word in modern English.