Dai/daɪ/ Definition 1 of 4Pro Tip 1/2Regional Usage Used mostly around Venice, Italy, to mean a local person, not commonly used elsewhere. The restaurant was owned by a dai who knew everyone in town. Pro Tip 2/2Colloquial Term Casual or informal conversation is the setting where 'dai' would be used in this sense. At the cafe, the dai shared stories about his childhood.