MEANING
To establish a fact by checking or investigation.
Use it for
fact-finding; checking eligibility; identifying unknown conditionsSignal an investigation rather than an unsupported assumption.
Words that belong together
- ascertain the cause
- ascertain whether
- ascertain the extent
On the page
The survey sought to ascertain whether students had reliable internet access.
From the surviving letters, historians can ascertain the date of departure.
Before interpreting the result, ascertain how the sample was selected.
Nearby words
Related words
Word forms
- Base
- ascertain / ascertains
- Past tense
- ascertained
- Past participle
- ascertained
- Present participle
- ascertaining
Full tense & aspect guide
- Present
- ascertain / ascertains
- Present continuous
- am/is/are ascertaining
- Present perfect
- have/has ascertained
- Present perfect continuous
- have/has been ascertaining
- Past
- ascertained
- Past continuous
- was/were ascertaining
- Past perfect
- had ascertained
- Past perfect continuous
- had been ascertaining
- Future
- will ascertain / ascertains
- Future continuous
- will be ascertaining
- Future perfect
- will have ascertained
- Future perfect continuous
- will have been ascertaining
Choose the auxiliary that agrees with your subject. These are constructions of one word, not separate entries.
Usage notes
Primary category: academic. Formal; stronger than suspect or estimate but need not imply absolute certainty. Ascertain whether, how, or the extent of something. Verb inflections [base, third-person singular, past, past participle, -ing]: ascertain, ascertains, ascertained, ascertained, ascertaining.
Practice this word in a sentenceYour margin notes
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