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Webster 1828 Edition

ppr.

Shaking, as threatening a fall; vacillating; reeling; inclining.

tottering ‎(comparative more tottering, superlative most tottering)

wobbly

tottering

tottering ‎(plural totterings)

The movement of one who totters.
- George Moore
  Its faint descent tried the powers of the horse to keep back the car, and so feeble were his totterings that I began to fear we should miss the train […]

(not held or fixed securely and likely to fall over): precarious, rickety, shaky, unsteady, unsafe, unstable, wobbly