dis·si·dent/ˈdisidənt/Noun :A person who opposes official policy, esp. that of an authoritarian state.
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Origin of EQUIVALENT
Middle English, from Middle French or Late Latin; Middle French, from Late Latin aequivalent-, aequivalens, present participle of aequivalēre to have equal power, from Latinaequi- + valēre to be strong — more at wieldFirst Known Use: 15th century