any of an extinct order (Eurypterida) of large, aquatic arthropods of the Paleozoic Era, similar to the horseshoe crab and sometimes reaching a length of c. 1.8 m (c. 6 ft)
Origin of eurypterid; from Modern Latin Eurypterida ; from Classical Greek eurys, broad + pteron, feather, wing: so named from a pair of broad swimming appendages
Any of various large segmented aquatic arthropods of the order Eurypterida that existed from the Ordovician Period to the Permian Period, having a long tail often with a spinelike appendage at the tip. Also called sea scorpion.
Origin of eurypteridFrom New Latin Eurypterida, order name, from Eurypterus, genus name : eury– + Greek pteron, wing; see –pter.