teachless

From teach +‎ -less.

teachless (comparative more teachless, superlative most teachless)

1. (archaic) Not teachable; incorrigible.
   • 1818-1819, Percy Bysshe Shelley, Julian and Maddalo

     […] if man be
     The passive thing you say, I should not see
     Much harm in the religions and old saws
     (Tho' I may never own such leaden laws)
     Which break a teachless nature to the yoke.

• “teachless”, in Webster’s Revised Unabridged Dictionary, Springfield, Mass.: G. & C. Merriam, 1913, →OCLC.

• cheatless