下寒武统 (下寒武統) xiàhánwǔ tǒng
          
              xiàhánwǔ tǒng 
              
              proper noun 
              lower Cambrian series 
              Domain: Modern Chinese 现代汉语
              
                , Subdomain: Geology 
              
              
                , Concept:  
              
              
              
                Notes: Geological strata from approx 530 million years ago (CC-CEDICT '下寒武統')