nuculoid
/ˌnjuːkjʊˈloʊɪd/Definitions
1. noun
A type of small, primitive saltwater clam, especially one of the family Nuculidae.
“The beachcomber discovered a nuculoid shell buried in the sand.”
2. adjective
Relating to or resembling the nuculoid clams.
“The paleontologist studied the nuculoid characteristics of the fossilized shells.”