An alumnus is someone who previously attended or graduated from a particular school, college or university orsomeone who had a former association with a particular organization. (noun)
An example of an alumnus is someone who graduated from Harvard.
An example of an alumnus is someone who previously worked for a specific large company.
☆ a person, esp. a boy or man, who has attended or is a graduate of a particular school, college, etc.
See alumnus in American Heritage Dictionary 4
(ə-lŭmˈnəs)
nounpl.a·lum·ni(-nīˌ)
A male graduate or former student of a school, college, or university.
Usage Note: Alumnus and alumna both come from Latin and preserve Latin plurals. Alumnus is a masculine noun whose plural is alumni, and alumna is a feminine noun whose plural is alumnae. Coeducational institutions usually use alumni for graduates of both sexes. But those who object to masculine forms in such cases may prefer the phrase alumni and alumnae or the form alumnae/i, which is the choice of many women's colleges that have begun to admit men.