The Collaborative International Dictionary of English v.0.48:

Laelaps \L[ae]"laps\ (l[=e]"l[a^]ps), n. [NL., fr. Gr. lai^laps
   a dark, furious storm.] (Paleon.)
   A genus of huge, carnivorous, dinosaurian reptiles from the
   Cretaceous formation of the United States. They had very
   large hind legs and tail, and are supposed to have been
   bipedal. Some of the species were about eighteen feet high.
   [1913 Webster]