The lyrics of "Stronger (What Doesn't Kill You)" by Kelly Clarkson convey a message of resilience and empowerment after hardship. Key parts of the lyrics include:

• "You think you got the best of me / Think you've had the last laugh / Bet you think that everything good is gone / Think you left me broken down / Think that I'll come running back / Baby, you don't know me, 'cause you're dead wrong."

• Chorus:
  "What doesn't kill you makes you stronger
  Stand a little taller
  Doesn't mean I'm lonely when I'm alone
  What doesn't kill you makes a fighter
  Footsteps even lighter
  Doesn't mean I'm over 'cause you're gone
  What doesn't kill you makes you stronger, stronger
  Just me, myself, and I."

• Verses and bridge reflect overcoming a breakup or difficult situation, starting anew, and gaining strength:
  "Thanks to you, I got a new thing started
  Thanks to you, I'm not the broken-hearted
  Thanks to you I'm finally thinking 'bout me
  You know in the end, the day you left was just my beginning."

The overall theme is that adversity and challenges, symbolized by what "doesn't kill you," lead to personal growth, strength, and independence rather than defeat or loneliness