C19: from Middle English titeren, related to Old Norse titra to tremble, Old High German zittarōn to shiver
Word Origin and History for teeter
v.
1843, "to seesaw," alteration of Middle English titter "move unsteadily," probably from Old Norse titra "to shake, shiver, totter," related to German zittern "to tremble." Noun teeter-totter "see-saw" is attested from 1905.