The Collaborative International Dictionary of English v.0.48:

Inure \In*ure"\, v. t. [imp. & p. p. Inured; p. pr. & vb. n.
   Inuring.] [From pref. in- in + ure use, work. See Ure
   use, practice, Opera, and cf. Manure.]
   To apply in use; to train; to discipline; to use or accustom
   till use gives little or no pain or inconvenience; to harden;
   to habituate; to practice habitually. "To inure our prompt
   obedience." --Milton.
   [1913 Webster]

         He . . . did inure them to speak little. --Sir T.
                                                  North.
   [1913 Webster]

         Inured and exercised in learning.        --Robynson
                                                  (More's
                                                  Utopia).
   [1913 Webster]

         The poor, inured to drudgery and distress. --Cowper.
   [1913 Webster]

         "Here the fortune of the day turned, and all things
         became adverse to the Romans; the place deep with ooze,
         sinking under those who stood, slippery to such as
         advanced; their armor heavy, the waters deep; nor could
         they wield, in that uneasy situation, their weighty
         javelins. The barbarians on the contrary, were inured
         to encounter in the bogs, their persons tall, their
         spears long, such as could wound at a distance." In
         this morass the Roman army, after an ineffectual
         struggle, was irrecoverably lost; nor could the body of
         the emperor ever be found. Such was the fate of Decius,
         in the fiftieth year of his age; . . .   --Gibbon
                                                  [quoting
                                                  Tacitus]
                                                  (Decline and
                                                  Fall of the
                                                  Roman Empire,
                                                  Ch. 10)
   [PJC]