不得

bùdé
  1. must not
  2. may not
  3. not to be allowed
  4. cannot

CEDICT

Entry Composition

1 不 bù
  1. no; not so
  2. (bound form) not; un-
=2 得 dé
  1. to obtain
  2. to get
  3. to gain
  4. to catch (a disease)
  5. proper
  6. suitable
  7. proud
  8. contented
  9. to allow
  10. to permit
  11. ready
  12. finished
=2 得 de structural particle: used after a verb (or adjective as main verb), linking it to following phrase indicating effect, degree, possibility etc