SPANISH

In Spanish the suffix dad is used for words ending in "ity". Ciudad is city, vanidad is vanity. So TRINIDAD means trinity.
The ordinary word for You is Usted. This is a short form of vuestra merced meaning "your grace". Merced is related to our word "mercy".

I suppose you could call this trivia. But I'd say that once you know lots more trivia like this, you can speak the language.