地下核爆炸 dìxiàhébàozhà underground nuclear explosion Origin Definitions Defs Strokes Stroke Words Sentences Sents 地下 dìxià nounlocative underground below the surface of the earth; subterranean; used to describe places or things located beneath the ground核爆炸 hébàozhà noun nuclear explosion A sudden and massive release of energy from a high-speed nuclear reaction; may result from fission, fusion, or both.