be off-limits

Definitions

Prohibited or forbidden from being entered, used, or accessed.

Not allowed to be discussed or considered as a topic.

Examples

The construction site is strictly off-limits to the public for safety reasons.

My personal diary is completely off-limits, so please do not try to read it.

Synonyms

prohibited forbidden out of bounds restricted taboo banned inaccessible

Antonyms

permitted allowed accessible open authorized unrestricted available