'Superorder' definitions:

Definition of 'superorder'

(from WordNet)
noun
(biology) a taxonomic group ranking above an order and below a class or subclass

Definition of 'Superorder'

From: GCIDE
  • Superorder \Su`per*or"der\, n. (Zool.) A group intermediate in importance between an order and a subclass. [1913 Webster]