ascertain

Verb

• learn or discover with certainty

• find out, learn, or determine with certainty, usually by making an inquiry or other effort
  • I want to see whether she speaks French
    
  • See whether it works
    
  • find out if he speaks Russian
    
  • Check whether the train leaves on time
    

• be careful or certain to do something; make certain of something
  • He verified that the valves were closed
    
  • See that the curtains are closed
    
  • control the quality of the product
    

• establish after a calculation, investigation, experiment, survey, or study
  • find the product of two numbers
    
  • The physicist who found the elusive particle won the Nobel Prize
    

Related words

• Synonyms: 
  determine , check , find out , see , watch , learn , insure , see to it , ensure , control , assure , find