The Collaborative International Dictionary of English v.0.48:

Ulterior \Ul*te"ri*or\, a. [L., comp. of ultra, ultro, beyond,
   on the other side, properly cases of an old adjective, formed
   with a comparative suffix, which is akin to OL. uls beyond,
   L. olim formerly, hereafter, orig., at that time, ille that,
   OL. olle, ollus. Cf. Outrage.]
   1. Situated beyond, or on the farther side; thither; --
      correlative with hither.
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   2. Further; remoter; more distant; succeeding; as, ulterior
      demands or propositions; ulterior views; what ulterior
      measures will be adopted is uncertain.
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   Ulterior motive, Ulterior object or Ulterior aim, a
      motive, object or aim beyond that which is avowed.
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