Limuloidea /(lĭm`ū̇*loi"dē̇*ȧ)/

Lim·u·loi·de·a

Limuloidea

n. pl.
  1. An order of Merostomata, including among living animals the genus Limulus, with various allied fossil genera, mostly of the Carboniferous period. Called also Xiphosura. (Zool.)