seesaw (see-saw)
noun, verb

noun
1. a long plank balanced in the middle on a fixed support, on each end of which children sit and swing up and down by pushing the ground alternately with their feet.
“This week some swings and see-saws have been put in the children’s playground”

1.1 a situation characterized by rapid, repeated changes from one state or condition to another.
    ‘the emotional see-saw of a first love affair’

verb
1. to change rapidly and repeatedly from one position, situation, or condition to another and back again.
“the market see-sawed as rumours spread of an imminent cabinet reshuffle”

The Oxford Dictionary

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ORIGIN

Mid 17th century, originally used by sawyers (Holzsäger) as a rhythmical refrain: reduplication of the verb saw (symbolic of the sawing motion).

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In most of the United States, a seesaw is also called a “teeter-totter”. According to linguist Peter Trudgill, the term originates from the Nordic language word tittermatorter. A “teeter-totter” may also refer to a two-person swing on a swing seat, on which two children sit facing each other and the teeter-totter swings back and forth in a pendulum motion.

Both teeter-totter (from teeter, as in to teeter on the edge) and seesaw (from the verb saw) demonstrate the linguistic process called reduplication, where a word or syllable is doubled, often with a different vowel. Reduplication is typical of words that indicate repeated activity, such as riding up and down on a seesaw.

In the southeastern New England region of the United States, it is sometimes referred to as a tilt or a tilting board.

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SYNONYMS

alter, alternate, change,  ebb and flow, fluctuate, go up and down, go to and fro, oscillate, rise and fall, swing, teeter, vary, veer, waver

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SMUGGLE OWAD into a conversation, say something like:

“Some leading politicians are just SEE-SAWING from one position to another, don't you think?”

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Many thanks to Florian for suggesting today’s OWAD