1. gracious (defeat, apology, etc.); graceful; honourable (e.g. death); noble; gallant; brave; manly; sportsmanlike
敗北したのなら、悔しくても潔く認めるしかない。If you've lost, all you can do is accept it gracefully, however frustrating it is.
2. upright; righteous; honest; pure (heart); innocent
3. unspoiled (scenery, etc.); pure; clean