Chiesa ( Church in Italian languge) . What's the origin of this word?

Answer 1

It comes from the Latin word "ecclesia" (and the Greek "ekklesia").
In Italian the term 'Chiesa' has 3 different meanings:
1.- The religious building where are performed the religious rites.
2.- The religious Institution (Chiesa Cattolica for istance) that gives the rules of its own religion and manages all the relevant actions.
3.- The community of all the believers of the same religion (and this was the original acception of the terms ecclesia / ekklesia)