The definition of an alumnus is someone who previously attended or graduated from a particular school, college or university or someone who had a former association with a particular organization.(noun)
See alumnus in Webster's New World College Dictionary
See alumnus in American Heritage Dictionary 4
noun pl. a·lum·ni (-nīˌ)
Origin: Latin, pupil
Origin: , from alere, to nourish; see al-2 in Indo-European roots. 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.
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