Word
ascertain
Phoneticsas·cer·tain, stress on the third syllable
US/ˌæsɝˈteɪn/
UK/ˌæsətˈeɪn/
Definitions
01to find out facts
C1 · Advanced Formal
v. to find out the true facts about a situation or a piece of information.
v. to discover or determine something with certainty; to establish a fact through investigation.
“The police are trying to ascertain the cause of the fire.”
“The committee conducted a thorough investigation to ascertain whether the safety protocols had been followed correctly during the emergency.”
02to make sure
C2 · Proficiency Archaic · Formal
v. to make sure that something happens or is true.
v. to ensure or make certain of an outcome or a fact.
“The contract was written to ascertain that both parties received equal payment.”
“The ancient laws were designed to ascertain the rights of the landowners against any claims from the crown.”
Usage
The verb is transitive and often followed by a 'that' clause or a 'wh-' clause (e.g., 'ascertain whether', 'ascertain how').
Real-World Examples
“It only recently became possible to ascertain a more precise date thanks to new tree ring records from similar elevations in the Pacific Northwest.” “Our most striking discovery was ascertaining that painted pottery production continued by constantly evolving.” Etymology
From Middle English acerteynen, from Old French acertener, from a- (“to, towards”) + certener (“make sure of”), from the adjective certain, from Latin certus (“certain, fixed”). Compare to Spanish acertar.
Etymology adapted from Wiktionary, available under CC BY-SA 4.0.
- Exam level
- CambridgeCambridgeCambridge English QualificationsThe exam suite from Cambridge University Press & Assessment, from A1 Movers up to C2 Proficiency. The benchmark names double as CEFR labels.C1 AdvancedIELTSIELTSInternational English Language Testing SystemThe 0–9 band test co-owned by the British Council, IDP, and Cambridge. Used for university entry, work, and migration.7.0–8.0TOEFL iBTTOEFL iBTTest of English as a Foreign Language, Internet-Based TestETS's academic English test, the standard route for US university admissions. Scored 0–120, with a 1–6 scale since 2026.1–6 scale: 5.0–5.595–113TOEICTOEICTest of English for International CommunicationETS's workplace English test, big in Japan and Korea. Listening & Reading scores 10–990 and tops out at C1.945–990
- Frequency
- Frequent
- Level
- C1 · Advanced
- Updated
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