What is the meaning of vacillating?

verb

• Be undecided about something; waver between conflicting positions or courses of action.
  • usage: "He oscillates between accepting the new position and retirement"
  • synonyms: hover, vibrate, vacillate, oscillate
• Move or sway in a rising and falling or wavelike pattern.
  • usage: "the line on the monitor vacillated"
  • synonyms: fluctuate, vacillate, waver

adjective

• Uncertain in purpose or action.
  • synonyms: vacillant, wavering