off limits

/ˈɔfˌlɪmɪts/
adjective
  1. Not allowed to be entered, used, or accessed; forbidden.
    • The teacher said the storage room is off-limits to students.
    • The construction site is off-limits to anyone without a hard hat.
    • That area of the park is off-limits after dark.
  2. Not permitted to be discussed or mentioned; taboo.
    • His past mistakes are off-limits in conversation.
    • The topic of salary is off-limits in many workplaces.
    • Politics is off-limits at family dinners to avoid arguments.
Antonyms
What does "off limits" mean? | whatsthatwordmean | whatsthatwordmean