单词 unionid 释义 unionid Zool.|junnd|[a. mod.L. Unionid- (see def.), f. L. unio unio: see -id3.]A member of the Unionid, a large family of bi-valve molluscs typified by the genus Unio of freshwater mussels; a unio.1861P. P. Carpenter in Rep. Smithsonian...