alum

plural alums · alternative alumn

1. countableuncountableAn astringent salt, usually occurring in the form of pale crystals, much used in the dyeing and tanning trade and in certain medicines, and now understood to be a double sulphate of potassium and aluminium (K₂SO₄·Al₂(SO₄)₃·24H₂O).First known use 14th c.

   A natural astringent and antiseptic, potassium alum was coveted for its medicinal and cosmetic properties.

   2011, Thomas Penn, Winter King, Penguin, published 2012, page 201

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   Venice also needed alum for trade, since it was the point of departure for overland transportation of alum to southern Germany and its cloth-manufacturing Free Cities.

   1991, Felix Gilbert, The Pope, His Banker, and Venice, page 80

2. countableuncountablechemistryAny similar double sulphate in which either or both of the potassium and aluminium is wholly or partly replaced by other univalent or tervalent cations.First known use 17th c.

   For similar reasons, aluminium sulphate and alums are used in dyeing cloth.[…]Normally alums are soluble in water and insoluble in alcohols.

   2000 June, Competition Science Vision, page 486

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   With weld and cochineal, which are colouring matters the most sensible to the action of sulphate of iron, the purified alums gave us colours more brilliant, fresh, and in a slight degree lighter; while those with our common alums were all duller, and evidently of a deeper hue.

   1807, William Nicholson, editor, A Journal of Natural Philosophy, Chemistry, and the Arts, volume XVIII, page 286

   In structure, the alums consist of simple ions, being not complexes, but double salts. Potash alum or potassium alum is the common alum, with the formula KAl(SO₄)₂·12H₂O) which, for convenience, may be written K₂SO₄·Al₂(SO₄)₃·24H₂O

   2005, Amit Arora, Text Book Of Inorganic Chemistry, page 386

present singular third person alums · participle present aluming · participle past alumed · past alumed · alternative alumn

1. transitiveTo steep in, or otherwise impregnate with, a solution of alum; to treat with alum.

   After drying, the cloth was alumed and finally dyed.

   1979, Kax Wilson, A History of Textiles, Westview Press, →ISBN, page 90

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   The silk should be boiled at the rate of 20 parts of soap per cent. , and then alumed. The aluming need not be so strong as for the fine crimson

   1839, Andrew Ure, A Dictionary of Arts, Manufactures, and Mines

plural alums · plural alumni · alternative alumn

1. CanadaUSA past attendee or graduate (of any gender) of a college, university or other educational institution.

   1961 Spring, Anchora of Delta Gamma, Volume LXXVII, No. 3, page 59, Evanston-North Shore alums are happy to open their homes to Sigma actives for special social events.

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   You'll remember that we're starting with a list of slightly over 7,000 names that are alums (most of them over 50) that we'd like to whittle down to a manageable list of prospects.

   2006, Ted Hart, James M. Greenfield, Pamela M. Gignac, Christopher Carnie, Major Donors: Finding Big Gifts in Your Database and Online, page 47

   All schools that last have alums, and, ancient as it was by American standards, Trinity by mid-century had thousands.

   2009, Timothy C. Jacobson, Charity & Merit: Trinity School at 300, page 190

   “It breaks my heart to see them naked, undignified, shivering in the cold as they swallow our daily filth,” proclaims the woman, played by the Saturday Night Live alum Aidy Bryant.

   2024 June 5, Shirley Li, “This Show Understands the Absurdity of Modern Existence”, in The Atlantic, archived from the original on 05 Jun 2024

   While presidential elections have been marred by mudslinging since the early Republic, these USC alums deployed a particular type of dirty tricks: what became known as “ratf--king,” or the use of unscrupulous tactics to interfere with the campaigns of opponents. The tactics pioneered by members of Trojans for Representative Government and later CREEP set a precedent for the sort of organized political sabotage that has become commonplace today in a digital world, especially for Republicans.

   2024 August 8, Jonathan van Harmelen, “The Little-Known Group That Pioneered Watergate’s Dirty Tricks—and Changed American Politics”, in TIME, archived from the original on 14 Aug 2024

   Synonyms: alumni, alumnx