The Free On-line Dictionary of Computing (30 December 2018):

Flavors

    A Lisp variant for the LISP Machine, with
   object-oriented features, developed by D. Weinreb and D.A. Moon
    in 1980.  "Classes" were called
   Flavors in the language.

   Though the Flavors design was superseded (notably by the Common
   LISP CLOS facility), the term "flavor" persisted as a general
   synonym for "class".

   ["Object-Oriented Programming with Flavors", D.A. Moon, SIGPLAN
   Notices 21(11):1-8 (OOPSLA '86), Nov 1986].

   (1994-12-01)