showing no sympathy or kind treatment synonym cruel毫不怜悯的;无情的;残忍的 a merciless killer/attack 无情的杀手/攻击 the merciless heat of the sun 太阳的酷热 She was subjected to the merciless criticism of her opponents. 她受到对手无情的批评。 It brought relief from the merciless summer heat. 它可以让人们摆脱夏日的酷热。