There are several definitions of the word patron (noun). The following two definitions are the most commonly used: 1. a person who is a customer, client, or paying guest, especially (esp.). a regular one, of a store, hotel, restaurant, or similar kind of business. 2. a person who supports with money, gifts, efforts, or endorsement an artist, writer, museum, cause, charity, institution, special event, or the like: e.g. a patron of the arts; patrons of the hotel or restaurant. Definition 1 tells us that a patron is a customer of a business. When we want to say that the patron is a regular customer (comes, stays, visits, shops or buys often) then we can refer to the patron as a "regular" (short form meaning "regular customer or regular patron).