tertiate

from The Collaborative International Dictionary of English v.0.48

Tertiate \Ter"ti*ate\, v. t. [L. tertiatus, p. p. of tertiare to
   do for the third time, fr. tertius the third.]
   1. To do or perform for the third time. [Obs. & R.]
      --Johnson.
      [1913 Webster]

   2. (Gun.) To examine, as the thickness of the metal at the
      muzzle of a gun; or, in general, to examine the thickness
      of, as ordnance, in order to ascertain its strength.
      [1913 Webster]