This word is acceptable for play in the UK dictionary that is being used in the following games:

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adj. Not steadfast; wavering, unfaithful.

Notsteadfast; not firmly fixed or established.

Not firmly adhering to a purpose; inconstant; irresolute.

Insecure; unsafe.

"He looked a moment at his "unsteadfast footing," then let his gaze wander to the swirling water of the stream racing madly beneath his feet."

steadfast   

underhanded    crowd    earthquake-created    variable-speed    extendable