Also, have a good day; have a good one. A cordial goodbye to you. For example, Thanks for the order, have a nice day, or See you next week--have a good day, or The car's ready for you--have a good one. These expressions have become synonymous with a polite farewell. The first originated about 1920 but, like the variants, became widespread only after 1950.

The American Heritage® Dictionary of Idioms by Christine Ammer. Copyright © 1997 by The Christine Ammer 1992 Trust. Published by Houghton Mifflin Company. All rights reserved.