'Taboo' is Tongan for 'sacred, forbidden' — brought to English by Captain Cook in 1777.
A social or religious custom prohibiting or forbidding discussion of a particular practice or forbidding association with a particular person, place, or thing.
From Tongan 'tabu' or 'tapu' (sacred, forbidden, set apart), introduced to English by Captain James Cook in 1777 after his voyages to Polynesia. Cook wrote in his journal: 'Not one of them would sit down, or eat a bit of any thing... On expressing my surprize at this, they were all taboo, as they said.' The Polynesian concept encompasses both the sacred and the forbidden — that which is set apart from ordinary use. Related to Hawaiian 'kapu,' Maori 'tapu,' and Samoan 'tapu.'
Captain Cook introduced 'taboo' to Europe after visiting Tonga in 1777 — one of the very few Polynesian words to enter global vocabulary (others include 'tattoo' from Tahitian 'tatau' and 'wiki' from Hawaiian). The Polynesian concept is richer than the English word suggests: 'tapu' unifies the sacred and the forbidden, recognizing that what is holy is also untouchable. Sigmund Freud's 1913 book 'Totem and Taboo' brought the word into psychoanalytic theory,