Mistempered, 1) compounded and hardened to an ill end: “throw your m. weapons to the ground,” Rom. I, 1, 94 (cf. Temper, subst. and vb.).
2) ill tempered, ill mixed, diseased, irritated (quibbling): “this inundation of m. humour rests by you only to be qualified,” John V, 1, 12.