You can pretty much work these out from the dictionary definitions of the individual words, but I appreciate your bemusement, especially where there are multiple meanings. These are the appropriate definitions from M-W online:

"minimalist" = of, relating to, or done in the style of minimalism; "minimalism" = a style or technique (as in music, literature, or design) that is characterized by extreme spareness and simplicity

"boutique" =  a small company that offers highly specialized services or products

"joint" =  a shabby or disreputable place of entertainment [though here I do not believe that "shabby" and "disreputable" are necessarily being emphasised; it could pretty much just be a slang word for "place"]

"swank" = characterized by showy display; fashionably elegant

"party" = a social gathering

"scene" = sphere of activity

"celebrity" = a famous or celebrated person

"set" =  a group of persons associated by common interests 

Pb03

“What I wanted to know was this : what does "boutique hotel" mean?
Does that refer to a hotel which has some shops inside ?”

Oh, I see the confusion. No, I don't think it means that. The "small company" in the M-W "boutique" definition that I cited is the hotel itself, not some other business that carries on inside or in association with the hotel.

This is from Wikipedia:

Boutique hotel is a term popularised in North America and the United Kingdom to describe intimate, usually luxurious or quirky hotel environments. Boutique hotels differentiate themselves from larger chain/branded hotels and motels by providing personalized accommodation and services / facilities.

This more or less accords with my understanding of the term.