plural of crystal class

(crystallography) Any of 32 possible classes of crystals, arising from the 32 possible combinations of symmetry operations.

plural of third class

(computing, object-oriented programming) Alternative form of superclass / (taxonomy) Alternative form of superclass

plural of super class

(sociology) A participant in class warfare.

plural of class warrior

(regular expressions) Characters which are excluded in a pattern.

(aviation, travel) (in a reservation system) The letter used to signify a particular fare level.

(martial arts) A division of competition used to match competitors against others of their own weight