Nitwits are translated as bad words on some of the spanish translations. The only acceptable translation is from spanish (Spain), "Simplón". I report this because I'm an spanish speaker and I can tell which of those are bad or good translations, and I don't know how those bad words made into the game in first place.

How to reproduce?

Write the following command: /say @e[type=villager]

I note the bad words:
 

1. es_ve (venezuela): Tonto (Bad word)
2. 
   es_uy (uruguay): Idiota (Seriously bad word)
3. 
   es_mx (mexico): Imbécil (Seriously bad word)
4. 
   es_es (spain): Simplón
5. 
   es_ec (ecuador): Imbécil (Seriously bad word)
6. 
   es_cl (colombia): Imbécil (Seriously bad word)
7. 
   es_ar (argentina): Idiota (Seriously bad word)