To move back and forth or from side to side, as if about to fall
(Verb)
Move hesitatingly, as if about to give way
(Verb)
Synonyms:
  1. falter
To change one's attitudes or policies, for example
(Verb)
Synonyms:
  1. swing
  2. vacillate
Give off unsteady sounds, alternating in amplitude or frequency
(Verb)
Synonyms:
  1. quaver
To move unsteadily back and forth:
(Verb)
Synonyms:
  1. swing