The Collaborative International Dictionary of English v.0.48:

Prolong \Pro*long"\, v. t. [imp. & p. p. Prolonged; p. pr. &
   vb. n. Prolonging.] [F. prolonger, L. prolongare; pro
   before, forth + longus long. See Long, a., and cf.
   Prolongate, Purloin. ]
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   1. To extend in space or length; as, to prolong a line.
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   2. To lengthen in time; to extend the duration of; to draw
      out; to continue; as, to prolong one's days.
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            Prolong awhile the traitor's life.    --Shak.
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            The unhappy queen with talk prolonged the night.
                                                  --Dryden.
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   3. To put off to a distant time; to postpone. --Shak.
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