The Collaborative International Dictionary of English v.0.48:

Seesaw \See"saw`\, n. [Probably a reduplication of saw, to
   express the alternate motion to and fro, as in the act of
   sawing.]
   1. A play among children in which they are seated upon the
      opposite ends of a plank which is balanced in the middle,
      and move alternately up and down.
      [1913 Webster]

   2. A plank or board adjusted for this play.
      [1913 Webster]

   3. A vibratory or reciprocating motion.
      [1913 Webster]

            He has been arguing in a circle; there is thus a
            seesaw between the hypothesis and fact. --Sir W.
                                                  Hamilton.
      [1913 Webster]

   4. (Whist.) Same as Crossruff.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Seesaw \See"saw`\, v. i. [imp. & p. p. Seesawad; p. pr. & vb.
   n. Seesawing.]
   To move with a reciprocating motion; to move backward and
   forward, or upward and downward.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Seesaw \See"saw`\, v. t.
   To cause to move backward and forward in seesaw fashion.
   [1913 Webster]

         He seesaws himself to and fro.           --Ld. Lytton.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Seesaw \See"saw`\, a.
   Moving up and down, or to and fro; having a reciprocating
   motion.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Crossruff \Cross"ruff`\ (-r?f`), n. (Whist)
   The play in bridge or whist where partners trump each a
   different suit, and lead to each other for that purpose; --
   called also seesaw.
   [1913 Webster]

WordNet (r) 3.0 (2006):

seesaw
    n 1: a plaything consisting of a board balanced on a fulcrum;
         the board is ridden up and down by children at either end
         [syn: seesaw, teeter, teeter-totter, teetertotter,
         teeterboard, tilting board, dandle board]
    v 1: ride on a plank [syn: teeter-totter, teetertotter,
         seesaw]
    2: move up and down as if on a seesaw
    3: move unsteadily, with a rocking motion [syn: teeter,
       seesaw, totter]

Moby Thesaurus II by Grady Ward, 1.0:

114 Moby Thesaurus words for "seesaw":
   Ferris wheel, Lissajous figure, alternate, alternately,
   alternation, back and fill, back and forth, back-and-forth,
   backward and forward, backwards and forwards,
   battledore and shuttlecock, cant, carousel, chute-the-chutes,
   chutes, coaction, come and go, coming and going,
   complementary distribution, concurrence, cooperation, ebb and flow,
   engagement, flounder, fluctuate, flux and reflux, flying horses,
   go through phases, hitch and hike, in and out, incline,
   interaction, interchange, intercommunication, intercourse,
   interlacing, intermeshing, interplay, intertwining, interweaving,
   interworking, lean, list, lurch, merry-go-round, mesh, meshing,
   metronome, mutatis mutandis, off and on, oscillate, oscillator,
   pass and repass, pendulate, pendulum, pitch, quid pro quo,
   reciprocal, reciprocally, reciprocate, reciprocation,
   reciprocative, rhythmic play, ride and tie, ring the changes, rock,
   rocker, rocking chair, rocking stone, roll, roller coaster,
   round and round, roundabout, seesawing, shift, shuffle, shuttle,
   shuttlecock, shuttlewise, sine wave, stagger, swag, sway, swing,
   teeter, teeter-totter, teeter-tottering, teeterboard, teetering,
   teetery-bender, tilt, tilter, tit for tat, to and fro, to-and-fro,
   totter, tottering, turn, up and down, up-and-down, ups and downs,
   vacillate, vary, vibrator, vice versa, waver, wax and wane, whip,
   whirligig, wibble-wabble, wigwag, wobble, yaw, zigzag



The Free On-line Dictionary of Computing (30 December 2018):

SEESAW

    An early system on the IBM 701.

   [Listed in CACM 2(5):16 (May 1959)].

   (1994-12-15)