Also called potash alum, potassium alum. a crystalline solid, aluminum potassium sulfate, K2SO4⋅Al2(SO4)3⋅24H2O, used in medicine as an astringent and styptic, in dyeing and tanning, and in many technical processes.
one of a class of double sulfates analogous to aluminum potassium sulfate, as aluminum ammonium sulfate, having the general formula R2SO4⋅X2(SO4)3⋅24H2O, where R is a univalent alkali metal or ammonium, and X one of a number of trivalent metals.
Other definitions for alum (2 of 3)
Other definitions for alum. (3 of 3)
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How to use alum in a sentence
Natasha Strain, an alum of the campus who works as a childcare worker and supervisor at the facility, is one of the plaintiffs listed in the suit.North County Report: San Pasqual Academy Supporters Sue to Stay Open | Kayla Jimenez | August 4, 2021 | Voice of San Diego
For Top Chef, that meant many challenges that took advantage of outdoor kitchens, a bubble of all-star alums replacing the usual rotating cast of guest judges and a brand-new approach to viewers’ beloved Restaurant Wars.Top Chef: Portland Was the Kindest Season Yet. Does the Finale Change That? | Elijah Wolfson | July 2, 2021 | Time
She is currently a senior director at Fairmont Consulting Group, a boutique management consulting firm in the aerospace and defense sector founded by fellow alums Jay Wynn, MBA ’04, and Ben Harper, MBA ’08, SM ’08.Meet the president: Annalisa Weigel ’94, ’95, SM ’00, PhD ’02 | Nicole Estvanik Taylor | June 30, 2021 | MIT Technology Review
In their MHS homes, alums said they were ranked by how well they did their chores and followed rules.
Natasha Strain, an alum of the campus, works as a childcare worker and supervisor at the facility.San Pasqual Academy Is Still Fighting for Its Life | Kayla Jimenez | May 10, 2021 | Voice of San Diego
A TNR alum dives deep in what happened with the 100-year-old institution.
And those who take issue with the ice bucket challenge have found an unexpected spokesperson in Jackass alum Steve-O.
Marine friends, all ranks and all mostly Anbar fighting alum, have been sending me emails as well.Their Fight…But Our Legacy: The New Battle for Fallujah | John Kael Weston | January 12, 2014 | THE DAILY BEAST
Apple alum Tony Fadell reinvented the boring market for home thermostats with his sleek and eco-savvy digital Nest.
Petraeus, himself a Sosh alum, became the central figure for a mix of reasons.The Petraeus Revolution: How He Changed the American Way of War | John Barry | January 8, 2013 | THE DAILY BEAST
If they require a second water put alum to that also as well as to the rinsing and blue water.The Ladies' Book of Etiquette, and Manual of Politeness | Florence Hartley
Thus the proportions are omitted, and alum becomes alum compound, whatever that may mean.
On examination it was found that the enclosure of the Atarrea was broken down, and the source saturated with alum.
The principal impurity, and one which renders alum unfit for the use of the dyer, is iron.
The applications of alum in the arts and manufactures are numerous and important.
British Dictionary definitions for alum
Also called: potash alum a colourless soluble hydrated double sulphate of aluminium and potassium used in the manufacture of mordants and pigments, in dressing leather and sizing paper, and in medicine as a styptic and astringent. Formula: K 2 SO 4 .Al 2 (SO 4) 3 .24H 2 O
any of a group of isomorphic double sulphates of a monovalent metal or group and a trivalent metal. Formula: X 2 SO 4 .Y 2 (SO 4) 3 .24H 2 O, where X is monovalent and Y is trivalent
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Scientific definitions for alum
Any of various crystalline double salts of a trivalent metal (such as aluminum, chromium, or iron) and a monovalent metal (such as potassium or sodium), especially aluminum potassium sulfate. Alum is widely used in industry as a hardener and purifier, and in medicine as an emetic and to stop bleeding.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.