To disenfranchise is defined as to take away someone's right to vote or to deprive someone of power, rights and privileges.(verb)
When certain segments of the population are deprived of their right to vote or of a position of power in society, this is an example of a time when you disenfranchise that segment of society.
See disenfranchise in Webster's New World College Dictionary
See disenfranchise in American Heritage Dictionary 4
transitive verb dis·en·fran·chised, dis·en·fran·chis·ing, dis·en·fran·chis·es
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