Definition of "aver"

A rare thing to ſee a yong man or woman, that liues idlely, and fares well, of what condition ſoeuer, not to bee in loue. Vbicumqꝫ ſecuritas, ibi libido dominatur, luſt & ſecurity domineere together, as St Hierome auerreth.

1624, Democritus Junior [pseudonym; Robert Burton], “Causes of Heroicall Loue, Temperature, Full Diet, Idlenesse, Place, Climat, &c.”, in The Anatomy of Melancholy: […], 2nd edition, Oxford, Oxfordshire: Printed by John Lichfield and James Short, for Henry Cripps, partition 3, section 2, member 2, subsection 1, page 209

Now as to the Scriptures being the Word of God, and evidently known to be ſo, or evidencing themſelves to be ſo, and that of right, and properly they are to be ſo called; all which thou J. O. very abſolutely averreſt, […]

1660, Samuel Fisher, “[Rusticus ad Academicos in Exercitationibus Expostulatoriis, Apologeticis Quatuor. The Rustick’s Alarm to the Rabbies: Or, The Country Correcting the University and Clergy, and (Not without Good Cause) Contesting for the Truth, against the Nursing Mothers and Their Children. In Four Apologetical and Expostulatory Exercitations; [...]] The Third Apologetical, and Expostulatory Exercitation”, in The Testimony of Truth Exalted, […], [London?: s.n.], published 1679, chapter I, page 411

Chiron, the four-legg'd Bard, had both / A Beard and Tail of his own growth; / And yet by Authors 'tis averr'd, / He made use onely of his Beard.

1662, [Samuel Butler], “[The First Part of Hudibras]”, in Hudibras. The First and Second Parts. […], London: […] John Martyn and Henry Herringman, […], published 1678; republished in A[lfred] R[ayney] Waller, editor, Hudibras: Written in the Time of the Late Wars, Cambridge: University Press, 1905, canto II, page 31

[T]he partial Infidel […] averreth the Sleep or Inſenſibility of the Soul both in good and bad perſons, from the time of their Deceaſe hence until their Reſurrection; […]

1701, Lawrence Smith, “[First Discourse on 2 Timothy 1:10]”, in The Evidence of Things Not Seen: Or, The Immortality of the Human Soul, and the Separate Condition thereof in the Other World, Asserted and Made Manifest: […], London: […] Thomas Speed, […], page 1

The Devil, I safely can aver, / Has neither hoof, nor tail, nor sting; / Nor is he, as some sages swear, / A spirit, neither here nor there, / In nothing—yet in everything.

1819, Percy Bysshe Shelley, “Peter Bell the Third”, in [Mary] Shelley, editor, The Poetical Works of Percy Bysshe Shelley. […], new edition, London: Edward Moxon […], published 1840, part the second (The Devil), stanza 1, page 239

An Irish author avers that the Earl of Leicester, on bended knees, did likewise present to her highness another horn, pertaining to a land beast of the unicorn nature.

1851 November 14, Herman Melville, “Cetology”, in Moby-Dick; or, The Whale, 1st American edition, New York, N.Y.: Harper & Brothers; London: Richard Bentley, page 156

As Coroner, I must aver, I thoroughly examined her. / And she's not only merely dead, she's really most sincerely dead.

1939 August 25, “Ding-Dong! The Witch Is Dead”, in Yip Harburg (lyrics), Harold Arlen (music), The Wizard of Oz (soundtrack), Metro-Goldwyn-Mayer

Horticulturalist Richard Lighty has a form [of Trillium grandiflorum] that he avers to open almost a cerise-red.

1997, Frederick W. Case, Jr., Roberta B. Case, “The North American Trilliums”, in Trilliums, Portland, Or.: Timber Press, page 109

In the meantime, on 5 June 2000, the applicant had brought a civil action against the Prosecutor's Office. He alleged that the termination of his contract had been unlawful and sought reinstatement and compensation for loss of salary. He averred, inter alia, that the climate in the Supreme Cassation Prosecutor's Office had deteriorated as a result of the actions of the Chief Prosecutor.

2007 July 26, European Court of Human Rights (Fifth Section), Peev v. Bulgaria (Application no. 64209/01)‎, Strasbourg, paragraph 19

[W]hen Yara tells him he picked the losing side, he avers that he might just as soon head back to the Iron Islands—"But first, I'm gonna fuck the queen" [...]

2019 April 14, Alex McLevy, “Winter is Here on Game of Thrones’ Final Season Premiere (Newbies)”, in The A.V. Club‎, archived from the original on 18 December 2020

[…] I return'd with ſimular proofe enough, / To make the Noble Leonatus mad, / By wounding his beleefe in her Renowne, / With tokens thus, and thus: auerring notes / Of Chamber-hanging, Pictures, this her Bracelet / (Oh cunning how I got) nay ſome markes / Of ſecret on her perſon, that he could not / But thinke her bond of Chaſtity quite crack'd, / I hauing tane the forfeyt.

1611 April (first recorded performance), William Shakespeare, “The Tragedie of Cymbeline”, in Mr. William Shakespeares Comedies, Histories, & Tragedies […] (First Folio), London: […] Isaac Iaggard, and Ed[ward] Blount, published 1623, [Act V, scene v], page 396, column 2

Upon a time the Body summon'd all the Members to meet in the Guild for the common good (as Aesops Chronicles averre many stranger Accidents) the head by right takes the first seat, and next to it a huge and monstrous Wen little lesse than the Head it selfe, growing to it by a narrower excrescency.

1641 May, John Milton, Of Reformation Touching Church-Discipline in England: And the Cavvses that hitherto have Hindred it; republished as Will Taliaferro Hale, editor, Of Reformation Touching Church-Discipline in England (Yale Studies in English; LIV), New Haven, Conn.: Yale University Press, 1916, 2nd book

[A]lthough thou averrest this, and averrest it truly, we are nevertheless constrained to plead guilty to the possession of so much of this sensibility [a refusal to hear details] (call it "sickly" if thou wilt) as that they case once proved, our feeling of duty refuses to sustain us any longer against that combined and overwhelming influence of shattered nerves and a sickened heart.

1841 December, R[ichard] R[obert] Madden, “Address on Slavery in Cuba, Presented to the General Anti-slavery Convention”, in The Churchman’s Monthly Review, London: R. B. Seeley and W. Burnside; and sold by L. and G. Seeley, […], page 705

[…] Gilbert has but two half-starved cowardly peasants to follow him, and but an auld jaded aver to ride upon, fitter for the plough than for manly service; […]

1820 March, [Walter Scott], chapter VIII, in The Monastery. A Romance. […], volume III, Edinburgh: […] Longman, Hurst, Rees, Orme, and Brown, […]; and for Archibald Constable and Co., and John Ballantyne, […], page 214