To waver is to sway back and forth, show doubt, or to become uncertain in your opinion or planned course of action.(verb)
When you decide on one option and then start to rethink your decision and have a hard time choosing, this is an example of a situation where you waver between different options.
See waver in Webster's New World College Dictionary
Origin: ME waveren, freq. of waven, to wave
See waver in American Heritage Dictionary 4
intransitive verb wa·vered, wa·ver·ing, wa·vers
Origin: Middle English waveren; see webh- in Indo-European roots.
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