Compounds of 琢

• 琢磨
  (n,vs) polish (jewels)
  cultivation
  (P)
• 彫琢
  (n,vs) carving and polishing
• 切磋琢磨
  (n,vs) cultivate one's character by studying hard
  diligent application
• 切磋琢磨し合う
  (exp) to work hard together
  to be in a state of friendly rivalry