rain out - Phrases/Idioms
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.
Force the cancellation or postponement of some event owing to bad weather. For example, Our picnic was rained out, but we hope to have it next week. [1920s]