The Collaborative International Dictionary of English v.0.48:
Syntactic \Syn*tac"tic\, Syntactical \Syn*tac"tic*al\, a. [Cf. G. ? putting together. See Syntax.] Of or pertaining to syntax; according to the rules of syntax, or construction. -- Syn*tac"tic*al*ly, adv. [1913 Webster]WordNet (r) 3.0 (2006):
syntactical adj 1: of or relating to or conforming to the rules of syntax; "the syntactic rules of a language" [syn: syntactic, syntactical]