ascertain

Verb

ascertain (third-person singular simple present ascertains, present participle ascertaining, simple past and past participle ascertained)

1. (transitive) To find out definitely; to discover or establish.
   • As soon as we ascertain what the situation is, we can plan how to proceed.
   • “There the cause of death was soon ascertained ; the victim of this daring outrage had been stabbed to death from ear to ear with a long, sharp instrument, in shape like an antique stiletto, which […] was subsequently found under the cushions of the hansom.[…]”1904–1905, Baroness Orczy [i.e., Emma Orczy], “The Tremarn Case”, in The Case of Miss Elliott, London: T[homas] Fisher Unwin, published 1905, →OCLC; republished as popular edition, London: Greening &...

   Synonyms:

   determine, discover, establish, find out, learn, work out, see, discern, assess

2. (obsolete, transitive) To make (someone) certain or confident about something; to inform.
   • Therfore the saide cõmissioners shall mowe say that nowe late during the parlement the King ascertaigned of the saide maliciouse pʳpose of his enemys, willed and desired the lords being then present to shewe their̃ good willes aide and helpe for the saide rescues[…]1436, Sir Nicholas Harris Nicolas, editor, Proceedings and Ordinances of the Privy Council of England, volume IV, published 1835, page 352c
   • We would most gladly ye came yourself if that ye may […] praying you to ascertain us of your News.1844 [1483], Caroline A. Halsted, quoting Richard III, chapter XV, in Richard III as Duke of Gloucester and King of England, page 307
3. (Yorkshire, dated, intransitive) To look for something lost.
4. (archaic, transitive) To establish, to prove.
   • The two firſt lines of the following book ſeem to aſcertain the true meaning of the concluſion of this, and to prove ſufficiently that by Ωκεανός here, Homer could not poſſibly intend any other than a river.1791, William Cowper, Homer’s Odyssey, volume II, book XI, page 274 (footnote)
   • In 1695 he [Walter Moyle] was chosen to represent the borough of Saltash in parliament ; a circumstance which ascertains the piece before us to have been written subsequent to that period.1800, Edward Malone, The Critical and Miscellaneous Prose Works of John Dryden, volume III, London: H. Baldwin and Son, page 382 (note 8)
5. (archaic, transitive) To ensure or effect.
   • It is true, that no diligence can aſcertain ſucceſs ; death may intercept the ſwifteſt career ; but he who is cut off in the execution of an honeſt undertaking, has at leaſt the honour of falling in his rank, and has fought the battle, though he miſſed the victory.1751 June 29, Samuel Johnson, The Rambler, volume III, number 134, London: A. Millar et al., published 1761, page 155
   • The ministry, in order to ascertain a majority in the house of lords, persuaded the queen to take a measure which nothing but necessity could justify.1757–65, Tobias Smollet, chapter X, in The History of England from the Revolution to the Death of George II, volume II, London: Richardson & Co., published 1830, page 224