The Collaborative International Dictionary of English v.0.48:

Second \Sec"ond\, v. t. [imp. & p. p. Seconded; p. pr. & vb.
   n. Seconding.] [Cf. F. seconder, L. secundare, from
   secundus. See Second, a.]
   1. To follow in the next place; to succeed; to alternate.
      [R.]
      [1913 Webster]

            In the method of nature, a low valley is immediately
            seconded with an ambitious hill.      --Fuller.
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            Sin is seconded with sin.             --South.
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   2. To follow or attend for the purpose of assisting; to
      support; to back; to act as the second of; to assist; to
      forward; to encourage.
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            We have supplies to second our attempt. --Shak.
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            In human works though labored on with pain,
            A thousand movements scarce one purpose gain;
            In God's, one single can its end produce,
            Yet serves to second too some other use. --Pope.
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   3. Specifically, (Parliamentary Procedure) to support, as a
      motion[6] or proposal, by adding one's voice to that of
      the mover or proposer.
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   Note: Under common parliamentary rules used by many
         organizations, especially legislative bodies, a motion
         must be seconded in order to come properly before the
         deliberative body for discussion. Any motion[6] for
         which there is no second[8] dies for lack thereof.
         [PJC]