Hello. I need to know more about the use of the word ritzy. Are the three following usage of this word correct/ wrong? “What a ritzy hotel”, “this is a ritzy gallery” and “my house is ritzy”
The Ritz is a hotel. So ritzy can certainly be applied to a hotel or other establishment.
You would be less likely to hear it about someone's house, but it is possible. Of course, one would not say this about one's own house.