The Collaborative International Dictionary of English v.0.48:

Synoptic \Syn*op"tic\, Synoptical \Syn*op"tic*al\, a. [Gr. ?:
   cf. F. synoptique. See Synopsis.]
   Affording a general view of the whole, or of the principal
   parts of a thing; as, a synoptic table; a synoptical
   statement of an argument. "The synoptic Gospels." --Alford.
   -- Syn*op"tic*al*ly, adv.
   [1913 Webster]