Definition of ascertain in US English:



[with object]
  • Find (something) out for certain; make sure of.

    ‘an attempt to ascertain the cause of the accident’
    with clause ‘management should ascertain whether adequate funding can be provided’
    • ‘The industry-institution interaction is basically aimed at ascertaining the requirements of the job market.’
    • ‘Much effort has been expended in attempting to ascertain a precise antecedent to the trust in other laws.’
    • ‘A team from the air accident investigation unit is still trying to ascertain the cause of the crash.’
    • ‘He will in due course be interviewed to ascertain his version of events.’
    • ‘It is an offence to determine the sex of the foetus under the cover of ascertaining the health of the unborn baby.’
    • ‘That should require interaction with leading and influential members of the community for ascertaining the views and problems of the community.’
    • ‘In the final report, the difficulties in ascertaining the number of deaths was referred to in detail.’
    • ‘There's an awkward pause as we try to ascertain the seriousness of the situation.’
    • ‘The village shop lady ascertains the quantity of cheese required, and cuts it for him.’
    • ‘He said the primary concern was ascertaining the healthcare needs of the patients.’
    • ‘The department in question could have ascertained her identity by looking at its own records.’
    • ‘It was further revealed that some officers would start their formality of ascertaining the number of students only after receiving the bribe amount.’
    • ‘As a result there are no references to ascertain the authenticity of many works.’
    • ‘It would be appreciated if you would ascertain this information in a timely manner.’
    • ‘He is now awaiting an insurance quote to ascertain the cost of repairing damage to both the statue and its foundations.’
    • ‘Efforts to ascertain concrete information are met with bland replies and you come away none the wiser.’
    • ‘A fire investigation team will try to ascertain the exact cause but it is thought to have been an electrical fault.’
    • ‘Moreover some of these physicians often issue a certificate of death before making a check up and ascertaining the cause of death.’
    • ‘A second objective was to attempt to ascertain the limits to survival in terms of loss of conductivity.’
    • ‘The same could be said about ascertaining the guilt.’
    find out, discover, come to know, get to know, work out, make out, fathom, fathom out, become aware of, learn, ferret out, dig out, dig up, establish, fix, determine, settle, decide, verify, make certain of, confirm, deduce, divine, intuit, diagnose, discern, perceive, see, realize, appreciate, identify, pin down, recognize, register, understand, grasp, take in, comprehend
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Late Middle English (in the sense ‘assure, convince’): from Old French acertener, based on Latin certus ‘settled, sure’.