The definition of former is something that happened in the past or a previously held role.(adjective)
See former in Webster's New World College Dictionary
Origin: ME formere, compar. of forme, first < OE forma: see foremost
See former in American Heritage Dictionary 4
Origin: Middle English
Origin: , comparative of forme, first
Origin: , from Old English forma; see per1 in Indo-European roots. Usage Note: Grammarians have often insisted that the phrases the former and the latter should be used only to refer to the first of two things and the second of two things, respectively, as in Ernest L. Thayer's “Casey at the Bat”: “But Flynn preceded Casey, as did also Jimmy Blake, and the former was a lulu and the latter was a fake.” It is easy to find violations of this rule in the works of good writers; nonetheless, many readers feel uneasy when the words are used in enumerations of more than two things, just as they would feel uneasy over the similar incorrect use of a comparative in a sentence such as Her boys are 7, 9, and 13; only the younger was born in California.
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