alum
(noun) a double sulphate of aluminum and potassium that is used as an astringent (among other things)
alumnus, alumna, alum, graduate, grad
(noun) a person who has received a degree from a school (high school or college or university)
alum, potassium alum, potash alum
(noun) a white crystalline double sulfate of aluminum: the potassium double sulfate of aluminum
alum, ammonia alum, ammonium alum
(noun) a white crystalline double sulfate of aluminum: the ammonium double sulfate of aluminum
Source: WordNet® 3.1
alum (countable and uncountable, plural alums)
An 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). [from 14th c.]
(chemistry) Any similar double sulphate in which either or both of the potassium and aluminium is wholly or partly replaced by other univalent or tervalent cations. [from 17th c.]
• (double sulphate of potassium and aluminum): potash alum
alum (third-person singular simple present alums, present participle aluming, simple past and past participle alumed)
(transitive) To steep in, or otherwise impregnate with, a solution of alum; to treat with alum.
alum (plural alums)
(shortening, Canada, US) A past attendee or graduate (of either gender) of a college, university or other educational institution.
• (of any gender): alumni (often proscribed), alumnx
• (the original Latin gender-specific loanwords): alumna (feminine), alumnus (of unspecified gender or masculine)
• Lamu, luma, malu, maul, mula
Source: Wiktionary
Al"um, n. Etym: [OE. alum, alom, OF. alum, F. alun, fr. L. alumen alum.] (Chem.)
Definition: 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.
Note: Common alum is the double sulphate of aluminium and potassium. It is white, transparent, very astringent, and crystallizes easily in octahedrons. The term is extended so as to include other double sulphates similar to alum in formula.
Al"um, v. t.
Definition: To steep in, or otherwise impregnate with, a solution of alum; to treat with alum. Ure.
Source: Webster’s Unabridged Dictionary 1913 Edition
9 May 2025
(noun) anything in accord with principles of justice; “he feels he is in the right”; “the rightfulness of his claim”
Coffee dates back to the 9th century. Goat herders in Ethiopia noticed their goats seem to be “dancing” after eating berries from a particular shrub. They reported it to the local monastery, and a monk made a drink out of it. The monk found out he felt energized and kept him awake at night. That’s how the first coffee drink was born.
