What is the meaning of taboo?

noun

• A prejudice (especially in Polynesia and other South Pacific islands) that prohibits the use or mention of something because of its sacred nature.
  • synonyms: tabu
• An inhibition or ban resulting from social custom or emotional aversion.
  • synonyms: tabu

verb

• Declare as sacred and forbidden.

adjective

• Excluded from use or mention.
  • usage: "forbidden fruit"; "in our house dancing and playing cards were out"; "a taboo subject"
  • synonyms: forbidden, out, prohibited, proscribed, tabu, verboten
• Forbidden to profane use especially in South Pacific islands.
  • synonyms: tabu