ratiocinatory

from The Collaborative International Dictionary of English v.0.48

Ratiocinatory \Ra`ti*oc"i*na*to*ry\
   (r[a^]sh`[i^]*[o^]s"[i^]*n[.a]*t[-o]*r[y^]), a.
   Ratiocinative. [R.]
   [1913 Webster]