taboo
     adj 1: excluded from use or mention; "forbidden fruit"; "in our
            house dancing and playing cards were out"; "a taboo
            subject" [syn: {forbidden}, {out(p)}, {prohibited}, {proscribed},
             {tabu}, {verboten}]
     2: forbidden to profane use especially in South Pacific islands
        [syn: {tabu}]
     n 1: a prejudice (especially in Polynesia and other South Pacific
          islands) that prohibits the use or mention of something
          because of its sacred nature [syn: {tabu}]
     2: an inhibition or ban resulting from social custom or
        emotional aversion [syn: {tabu}]
     v : declare as sacred and forbidden
Source: WordNet® 2.0