Merostomata \Mer`o*stom"a*ta\, n. pl. [NL., fr. Gr. ? thigh + ?,
-?, mouth.] (Zo["o]l.)
A class of Arthropoda, allied to the Crustacea. It includes
the trilobites, Eurypteroidea, and Limuloidea. All are
extinct except the horseshoe crabs of the last group. See
{Limulus}.
Merostomata
n : used in some classifications; includes the orders Xiphosura
and Eurypterida [syn: {class Merostomata}]