释义 |
uni·on·i·dae \ˌ ̷ ̷ ̷ ̷ˈänəˌdē\ noun plural Usage: capitalized Etymology: New Latin, from Union-, Unio, type genus + -idae : a very large family of freshwater mussels (suborder Submytilacea) having a pearly often roughly sculptured shell with a thick epidermis and larvae that pass through a glochidium stage and being represented in nearly all parts of the world but chiefly in No. America where the nacreous shells of many of them are used for button making |