Beastly foot has no right to wobble (6)
I believe the answer is:
totter
'wobble' is the definition.
(tottering is a kind of wobbling)
I don't understand the rest of the clue.
Can you help me to learn more?
(Other definitions for totter that I've seen before include "Move unsteadily; be about to fall" , "Sway, as if about to fall" , "adder?" , "Stand/walk unsteadily" , "Walk unsteadily as if about to collapse" .)