a large group of arthropods that comprises the arachnids, sea spiders, and horseshoe crabs. They lack antennae, but possess a pair of chelicerae, a pair of pedipalps, and (typically) four pairs of legs.
Subphylum Chelicerata, phylum Arthropoda
modern Latin (plural), from Greek khēlē 'claw' + keras 'horn'
Chelicerata in other Oxford dictionaries
Definition of Chelicerata in the US English dictionary