s-word

Short definition from Wiktionary

Noun

1. 1
   The word shit, regarded as a vulgar word.
2. 2
   The word slut, regarded as a vulgar word.
3. 3
   The word spastic, regarded as an offensive word.
4. 4
   The word spic, regarded as a vulgar word.
5. 5
   Any word beginning with s that is not normally taboo but is considered (often humorously) to be so in the given context; for example, socialism.