Definitions

from The Century Dictionary.

  • To steep in or impregnate with a solution of alum.
  • noun The general name of a class of double sulphates formed by the union of aluminium, iron, chromium, or manganese sulphate with the sulphate of some other metal, commonly an alkaline metal or ammonium.

from the GNU version of the Collaborative International Dictionary of English.

  • transitive verb To steep in, or otherwise impregnate with, a solution of alum; to treat with alum.
  • noun (Chem.) A double sulphate formed of aluminium and some other element (esp. an alkali metal) or of aluminium. It has twenty-four molecules of water of crystallization.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

  • verb transitive To steep in, or otherwise impregnate with, a solution of alum; to treat with alum.
  • noun US A graduate of a university or other institution.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • noun a white crystalline double sulfate of aluminum: the ammonium double sulfate of aluminum
  • noun a double sulphate of aluminum and potassium that is used as an astringent (among other things)
  • noun a white crystalline double sulfate of aluminum: the potassium double sulfate of aluminum
  • noun a person who has received a degree from a school (high school or college or university)

Etymologies

from Wiktionary, Creative Commons Attribution/Share-Alike License

From Anglo-Norman alum, alume et al., Middle French allume, from Latin alūmen ("alumen").

from Wiktionary, Creative Commons Attribution/Share-Alike License

From alumnus and alumna, by removal of the non-native, gender-specific endings.

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Examples

Comments

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  • "Alum has been used at least since Roman times for purification of drinking water and industrial process water. Between 30 and 40 ppm of alum for household wastewater, often more for industrial wastewater, is added to the water so that the negatively charged colloidal particles clump together into "flocs", which then float to the top of the liquid, settle to the bottom of the liquid, or can be more easily filtered from the liquid, prior to further filtration and disinfection of the water."

    -- Wikipedia (http://en.wikipedia.org/w/index.php?title=Alum&oldid=551044797)

    April 24, 2013

  • Adds a whole new meaning to alum-are-us. These

    are fields to be explored.

    April 25, 2013

  • Usage note in comment on cardinal purple. Another on Francesco Pegolotti.

    October 4, 2017