Definitions
1.NounA habitual patron, regular purchaser, returning client; a person or company who has a custom of buying from a particular business.
2.NounA patron, a client; a person or company who purchases or receives a product or service from a business or merchant, or intends to do so."Every person who passes by is a potential customer.; Airlines are the chief customers of the commercial divisions of large-aircraft manufacturers such as Airbus, Boeing, and Embraer."
3.NounA person, especially one engaging in some sort of interaction with others."a cool customer, a tough customer, an ugly customer"
4.NounA native official who exacted customs duties.