Xiphosura
WordNet
noun
(1) Horseshoe crabs and extinct forms
WiktionaryText
Etymology
From and , in reference to the long, slender, stiff tail of the horseshoe crab.
Proper noun
Xiphosura
- An order of the class Merostomata distinguished from all other chelicerates by having compound eyes. The only living xiphosurans are the horseshoe crabs.