hang out to dry - 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.
Abandon someone to danger, as in The squadron withdrew and just let us hang out to dry. This expression alludes to hanging wet laundry on a clothesline. [Slang; 1960s]