to say nothing of

• (Received Pronunciation) IPA^(key): /tʊ seɪ ˈnʌθɪŋ əv/
• (General American) IPA^(key): /tə seɪ ˈnʌθɪŋ əv/

• Audio (General Australian):

  (file)

• Hyphenation: to say no‧thing of

to say nothing of

1. (idiomatic) An apophasis used to mention another important, usually related, point: not taking into account, not to mention, without considering.

   She had already eaten a large lunch, to say nothing of a full cooked breakfast that morning.

   • 1716, M. R., “The Last Time of His Magistracy”, in W H D Longstaffe, editor, Memoirs of the Life of Mr. Ambrose Barnes, Late Merchant and Sometime Alderman of Newcastle upon Tyne (The Publications of the Surtees Society; L), Durham: Published for the Society, by Andrews & Co. , published 1867, →OCLC, page 174:

     The prodigies of this reign can scarce be paralelled in any reign. To say nothing of the King's sister the Dutchess of Orleance being poysoned, nor what was the occasion of it: to say nothing of the Queen Mother and Prince Rupert's leaving the Court in discontent: to say nothing of the thousands that dyed of the plague: to say nothing of the conflagration of London,

   • 1774 March, “11. A Political Survey of Britain; being a Series of Reflections on the Situation, Lands, Inhabitants, Revenues, Colonies, and Commerce of This Island. In Two Vols. By John Campbell, LL.D. Printed for the Author. ”, in Sylvanus Urban , editor, The Gentleman’s Magazine, and Historical Chronicle, volume XLIV, London: Printed , for D Henry, and sold by F Newbery, , →OCLC, page 132:

     In a word, there has hardly been any great event, in any part of Europe, in which the Britiſh crown by its miniſters, or the inhabitants of Britain by their valour, have not had a conſiderable part. Sir Thomas Chaloner attended the Emperor Charles V. in his African expedition. The Earl of Eſſex commanded the Engliſh auxiliaries in the ſervice of Henry IV. of France. To ſay nothing of our hoſtile expeditions, in ſupport of the claim of our monarchs to the crown of that kingdom; or of the aſſiſtances given to the French kings, in oppoſition to that claim by the Scots.

   • 1926 October, Richard Savage, “The Stage Mommer: Canny Adviser to Aspiring Offspring, but Not Overpopular with Company Manager”, in Arthur Hornblow , editor, Theatre Magazine, volume XLIV, number 307, New York, N.Y.: The Theatre Magazine Company , →OCLC, page 18:

     The Back-Stage Mother is difficult to evaluate. As a rule, you find her some place where she doesn't belong. If she is not standing in the wings to watch her adorable daughter perform, and thus interfering with the property-man, electrician, carpenter, stage manager, assistant stage manager and prompter, to say nothing of blocking an important entrance where players must push her out of the road to get onto the stage, she is almost certain to be out in front, cornering the company manager in the lobby.

   • 2018 February, Robert Draper, “They are Watching You—and Everything Else on the Planet: Technology and Our Increasing Demand for Security have Put Us All under Surveillance. Is Privacy Becoming just a Memory?”, in National Geographic‎, Washington, D.C.: National Geographic Society, →ISSN, →OCLC, archived from the original on 14 June 2018:

     Today more than 2.5 trillion images are shared or stored on the Internet annually—to say nothing of the billions more photographs and videos people keep to themselves.

• let alone
• not to mention
• much less

• apophasis