freshwater mussel fresh·wa·ter·mussel uncommon noun 1. bivalve mollusk abundant in rivers of central United States Synonymsfreshwater musselfreshwater clam Related words Broader terms mussel Narrower terms pearly-shelled musselthin-shelled musselzebra mussel WordNet 2.1 (Princeton University). WordNet 2.1 Copyright Princeton University. All rights reserved.
