adj., n., pl. -boos, adj.
1. proscribed by society as improper or unacceptable: taboo words.
2. set apart as sacred; forbidden for general use; placed under a prohibition or bar.n.
3. a prohibition or interdiction of something; exclusion from use or practice.
4. the system or practice of setting things apart as sacred or forbidden for general use.
5. exclusion from social relations; ostracism.v.t.
6. to put under a taboo; prohibit or forbid.
7. to ostracize.
[1770–80; < Tongan tapu or Fijian tabu]