taboo

nouns

a prejudice (especially in Polynesia and other South Pacific islands) that prohibits the use or mention of something because of its sacred nature
taboo, tabu
an inhibition or ban resulting from social custom or emotional aversion
taboo, tabu

verbs

declare as sacred and forbidden
taboo
is a type of (narrower)
place under restrictions; limit access to
"This substance is controlled"
restrict

adjectives

excluded from use or mention
"forbidden fruit"; "in our house dancing and playing cards were out"; "a taboo subject"
forbidden, out, prohibited, proscribed, taboo, tabu, verboten
forbidden to profane use especially in South Pacific islands
taboo, tabu