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
1
To find out or establish something for certain, usually through checking or investigation.
"As soon as we ascertain what the situation is, we can plan how to proceed."
"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 notesIn 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
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Word forms
- Third person singular
- ascertains
- Past tense
- ascertained
Fill the gap
Can you complete this real example?
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."
Synonyms
View more →Antonyms
Related words
Rhymes for ascertain
See all rhymes for ascertain →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.
