Taboo

A total prohibition of intercourse with, use of, or approach to, a given person or thing under pain of death, -- an interdict of religious origin and authority, formerly common in the islands of Polynesia; interdiction.

To put under taboo; to forbid, or to forbid the use of; to interdict approach to, or use of; as, to taboo the ground set apart as a sanctuary for criminals.

an inhibition or ban resulting from social custom or emotional aversion