linguistical

from The Collaborative International Dictionary of English v.0.48

Linguistic \Lin*guis"tic\ (l[i^][ng]*gw[i^]s"t[i^]k),
Linguistical \Lin*guis"tic*al\ (l[i^][ng]*gw[i^]s"t[i^]*kal), a.
   [Cf. F. linguistique.]
   Of or pertaining to language; relating to linguistics, or to
   the affinities of languages.
   [1913 Webster]