pho·lad·i·dae \fōˈladəˌdē\noun plural Usage: capitalized Etymology: New Latin, from Pholad-, Pholas, type genus + -idae : a family of bivalve mollusks (order Eulamellibranchia) comprising the piddocks and related borers • pho·la·doid\ˈfōləˌdȯid\adjective