'Eurypteroidea' definitions:

Definition of 'Eurypteroidea'

From: GCIDE

Eurypteroidea \Eu*ryp`te*roi"de*a\, n. pl. [NL. See Eurypteroid.] (Paleont.) An extinct order of Merostomata, of which the genus Eurypterus is the type. They are found only in Paleozoic rocks. [Written also Eurypterida.] [1913 Webster]