underfillingWiktionary 原文1词源 1词源说明See the etymology of the corresponding lemma form.释义（英文）动词 Verbpresent participle and gerund of underfill2词源 2构词拆分under-前缀Beneath, under · (figurative) To go from one side to the other; to progress along a path+filling词根/词干词源说明From under- + filling.释义（英文）名词 NounThe underneath structure of a building.