不客氣

不客气
bùkèqi
  1. you're welcome
  2. don't mention it
  3. impolite
  4. rude
  5. blunt

CEDICT

Entry Composition

1 不 bù
  1. no; not so
  2. (bound form) not; un-
2 客氣 kèqi
  1. polite
  2. courteous
  3. formal
  4. modest