Malcontent

Part of speech: noun (n.)

One who discontented; especially, a discontented subject of a government; one who express his discontent by words or overt acts. Spenser. Berkeley.

Part of speech: adjective (a.)

discontented; uneasy; dissatisfied; especially, dissatisfied with the government. [Written also malecontent.] The famous malcontent earl of Leicester. Milner.