lose one's shirt
Fig. to lose a lot of money; to lose all of one's assets (as if one had even lost one's shirt). I almost lost my shirt on that deal. I have to invest more wisely. No, I can't loan you $200. I just lost my shirt at the racetrack.
lose one's shirt
Face financial ruin, go bankrupt, as in He lost his shirt in the last recession. This expression implies one has lost even one's shirt. [Early 1900s]
lose (one's) shirt
Slang To lose everything one has or owns.
lose one's shirt, to
To lose everything. This term alludes to betting on or investing everything one owns in some venture, but at one time it meant to become very angry (in effect the opposite of keep your shirt on). The current cliché, aided and abetted by the Great Depression, is a twentieth-century locution. “He hit the market . . . about the time the bottom dropped out of it. He lost his shirt!” (E. B. Mann, Thirsty Range, 1935).