subclass

Subclass may refer to:Subclass (biology), a taxonomic rank intermediate between class and superorderSubclass (computer science), a class that is derived from another class or classesSubclass (database theory), a class which inherits its data members and methods of their superclassesSubclass (set theory), a class contained in some other class in the same way that a subset is a set contained in some other set.
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(n.)
One of the natural groups, more important than an order, into which some classes are divided; as, the angiospermous subclass of exogens.
  

derived class

Noun
1. (biology) a taxonomic category below a class and above an order
(hypernym) taxonomic group, taxonomic category, taxon
(classification) biology, biological science