give the shirt off one's back

give (someone) the shirt off (one's) back

To act in a very generous and selfless manner. I'm not surprised that Tammy loaned you money—she would give anyone the shirt off her back. Tom has given the shirt off his back to keep this charity operational.
See also: back, give, off, shirt
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

give the shirt off one's back

Give anything and everything one possesses. For example, Tom is truly generous-he'll give you the shirt off his back. This hyperbolic idiom was first recorded in 1771.
See also: back, give, off, shirt
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.

give the shirt off one's back, to

To give one’s all; the ultimate in generosity. This hyperbole appeared in Tobias Smollett’s novel of 1771, Humphry Clinker, and has been employed ever since. Elinor Wylie used it in her ironic poem “Portrait in Black Paint”: “She’d give the shirt from off her back except that she doesn’t wear a shirt.”
See also: give, off, shirt, to
The Dictionary of Clichés by Christine Ammer Copyright © 2013 by Christine Ammer
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