a recreation in which two children alternately ride up and down while seated at opposite ends of a plank balanced at the middle.

a plank or apparatus for this recreation.

an up-and-down or a back-and-forth movement or procedure.

Whist . a crossruff.

moving up and down, back and forth, or alternately ahead and behind

It was a seesaw game with the lead changing hands many times.

to move in a seesaw manner

The boat seesawed in the heavy sea.

to ride or play on a seesaw.

to keep changing one's decision, opinion, or attitude; vacillate.

to cause to move in a seesaw manner.

verb

pitch , roll , yaw , alternate , fluctuate , rock , sway , teeter , teeter-totter , vacillate , waver