[see.saw] n [prob. fr. redupl. of [3]saw] (1704) 1: an alternating up-and-down or backward-and-forward motion or movement; also: a contest or struggle in which now one side now the other has the lead
2. a: a pastime in which two children or groups of children ride on opposite ends of a plank balanced in the middle so that one end goes up as the other goes down b: the plank or apparatus so used -- seesaw adj
[2]seesaw vi (1712) 1 a: to move backward and forward or up and down b: to play at seesaw
2: alternate ~ vt: to cause to move in seesaw fashion