alum

Other forms of alum

plural

alums·

Forms marked · are formed by the regular rule rather than recorded in the source data. English keeps a few hundred irregulars and the rest follow the pattern, so the rule is right far more often than not — but it is a rule, and the mark says so.

Questions about alum

What does alum mean?

alum means "a white crystalline double sulfate of aluminum: the ammonium double sulfate of aluminum". That is the primary sense; the word has 4 in total, listed in full on this page.

How many syllables are in alum?

alum has 2 syllables: al-um. The stress falls on "al". In IPA it is /ˈæləm/.

What is another word for alum?

Close synonyms include ammonia alum, ammonium alum, potassium alum, potash alum, alumnus. Each sense on this page lists its own synonyms, because a word with several meanings rarely has one substitute that works for all of them.

Is alum a common word?

alum is banded "Uncommon" — turns up in careful writing rather than conversation. The band comes from how often the word appears in a large corpus of everyday English, not from an editor's impression.