1. [adj]  being the last or concluding element of a series; "the ultimate sonata of that opus"; "a distinction between the verb and noun senses of `conflict' is that in the verb the stress is on the ultimate (or last) syllable"
2. [adj]  furthest or highest in degree or order; utmost or extreme; "the ultimate achievement"; "the ultimate question"; "man's ultimate destiny"; "the ultimate insult"; "one's ultimate goal in life"
3. [adj]  being the ultimate or elemental constituents of anything; "the elemental stuff of...out of which the many forms of life have been molded"- Jack London; "the ultimate ingredients of matter"; "his proposal is elegantly simple"

Ultimate
Yardbirds: Ultimate!, The

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1. \Ul"ti*mate\, a. [LL. ultimatus last, extreme, fr. L.
   ultimare to come to an end, fr. ultimus the farthest, last,
   superl. from the same source as ulterior. See {Ulterior}, and
   cf. {Ultimatum}.]
   1. Farthest; most remote in space or time; extreme; last;
      final.
            My harbor, and my ultimate repose.    --Milton.
            Many actions apt to procure fame are not conductive
            to this our ultimate happiness.       --Addison.
   2. Last in a train of progression or consequences; tended
      toward by all that precedes; arrived at, as the last
      result; final.
            Those ultimate truths and those universal laws of
            thought which we can not rationally contradict.
                                                  --Coleridge.
   3. Incapable of further analysis; incapable of further
      division or separation; constituent; elemental; as, an
      ultimate constituent of matter.
   {Ultimate analysis} (Chem.), organic analysis. See under
      {Organic}.
   {Ultimate belief}. See under {Belief}.
   {Ultimate ratio} (Math.), the limiting value of a ratio, or
      that toward which a series tends, and which it does not
      pass.
   Syn: Final; conclusive. See {Final}.
   

2. \Ul"ti*mate\, v. t. & i. [imp. & p. p. {Ultimated}; p.
   pr. & vb. n. {Ultimating}.]
   1. To come or bring to an end; to eventuate; to end. [R.]
   2. To come or bring into use or practice. [R.]