customer

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. One that buys goods or services.
2. n. Informal An individual with whom one must deal: a tough customer.

Century Dictionary and Cyclopedia

1. n. A collector of customs; a toll-gatherer; a tax-gatherer.
2. n. One who purchases goods or a supply for any current need from another; a purchaser; a buyer; a patron, as of a house of entertainment.
3. n. A prostitute.
4. n. One who has special customs, as of the country or city.
5. n. Any one with whom a person has to deal; especially, one with whom dealing is difficult or disagreeable; hence, a fellow: as, a queer customer; a rough customer.
6. Being a customer or customers; purchasing; buying.
7. Made to the order of or for a customer; specially ordered by a customer and made for him: opposed to ready-made, or made for the market generally: as, customer work.

Wiktionary

1. n. A patron; one who purchases or receives a product or service from a business or merchant, or intends to do so.
2. n. informal A person, especially one engaging in some sort of interaction with others.

GNU Webster's 1913

1. n. obsolete One who collect customs; a toll gatherer.
2. n. One who regularly or repeatedly makes purchases of a trader; a purchaser; a buyer.
3. n. A person with whom a business house has dealings.
4. n. colloq. A peculiar person; -- in an indefinite sense.
5. n. obsolete A lewd woman.

WordNet 3.0

1. n. someone who pays for goods or services