Source : Webster's Revised Unabridged Dictionary (1913)

Teeter \Tee"ter\, v. i. & t. [imp. & p. p. {Teetered}; p. pr. &
   vb. n. {Teetering}.] [Prov. E. titter to tremble, to seesaw;
   cf. Icel. titra to tremble, OHG. zittar[=o]n, G. zittern.]
   To move up and down on the ends of a balanced plank, or the
   like, as children do for sport; to seesaw; to titter; to
   titter-totter. [U. S.]

         [The bobolink] alit upon the flower, and teetered up
         and down.                                --H. W.
                                                  Beecher.

Source : WordNet®

teeter
     v : move unsteadily, with a rocking motion [syn: {seesaw}, {totter}]