fair-weather friend

fair-weather friend idiom
A person who is dependable in good times but is not in times of trouble. For example, You can't rely on Sarah—she's strictly a fair-weather friend. This expression likens fair weather to good times. [Early 1700s]

The American Heritage® Dictionary of Idioms by Christine Ammer. Copyright © 2003, 1997 by The Christine Ammer 1992 Trust. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

Comments
Improve this definition.
Do you have more to add? Share your linguistic knowledge or observation.
/Register to save your comments.