refine

verb5

1. •
   To purify; reduce to a fine, unmixed, or pure state; to free from impurities.
2. •
   To improve in accuracy, delicacy, or excellence.
3. •
   To become pure; to be cleared of impure matter.
4. •
   To purify of coarseness, vulgarity, inelegance, etc.; to polish.

   • to refine someone's manners
   • to refine one's tastes
5. •
   To make nice or subtle.

   • to refine thought