patron saint       
noun [ C ] uk/ˌpeɪ.trən ˈseɪnt/ us/ˌpeɪ.trən ˈseɪnt/
 守护圣人,主保圣人
a Christian saint who is believed to give special help to a particular place, activity, person, or type of object
  St John Bosco is the patron saint of Turin. 圣约翰‧博斯科是都灵的主保圣人。