Uropygids

Part of speech: noun

Definitions

1. Members of an order of arachnids, often called whip scorpions, that have a long tail-like whip at the rear of the body
2. Small tailed arachnids belonging to the order Uropygi, which lack venom glands and defend themselves with acid spray
3. Arthropods of the order Uropygi, flat-bodied creatures with a slender whip-like tail that are nocturnal and live in warm regions

Etymology: Uropygids are arachnids of the order Uropygi, whose name comes from Greek "oura" (tail) and "pygē" (rump). The name points to the rear of the body, where these animals carry a long, whip-like tail appendage, which is why they are also called whip scorpions, though they are not true scorpions. "Uropygids" is simply the plural of "uropygid", one member of that order, so the final "-s" just counts several of these creatures.