alum

名词 alum:

1. a white crystalline double sulfate of aluminum: the ammonium double sulfate of aluminum
   同义词：ammonia alum, ammonium alum
2. a white crystalline double sulfate of aluminum: the potassium double sulfate of aluminum
   同义词：potassium alum, potash alum
3. a person who has received a degree from a school (high school or college or university)
   同义词：alumnus, alumna, graduate, grad
4. a double sulphate of aluminum and potassium that is used as an astringent (among other things)

alum 2

n.Informal （名词）【非正式用语】
An alumna or alumnus.
女校友、女毕业生，男校友、男毕业生