Things that are forbidden or prohibited by social custom or religious law, often considered too shameful or offensive to discuss openly.
From Tongan 'tabu' or 'tapu' meaning 'sacred' or 'forbidden,' adopted into English during colonial encounters in the Pacific Islands in the late 1700s. The word came to mean any social prohibition.
Interestingly, different cultures have completely opposite taboos—some cultures taboo discussing death while others taboo discussing money, which shows that taboos aren't based on universal morality but on what each society deems sacred.
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