Source : Free On-Line Dictionary of Computing

Common LISP Object System
     
        (CLOS) An {object-oriented} extension to {Common LISP}, based
        on {generic function}s, {multiple inheritance}, {declarative
        method combination} and a {meta-object protocol}.  A
        descendant of {CommonLoops} and based on {Symbolics} {FLAVORS}
        and {Xerox} {LOOPS}, among others.
     
        See also {PCL}.
     
        ["Common LISP Object System Specification X3J13 Document
        88-002R", D.G.  Bobrow et al, SIGPLAN Notices 23 (Sep 1988)].
     
        (1994-11-30)