Definition of lose one's shirtchiefly US, informal
- Many investors lost their shirts when the market crashed.
: to bring to destruction
: to miss from one's possession or from a customary or supposed place
: a garment for the upper part of the body: such as
: a cloth garment usually having a collar, sleeves, a front opening, and a tail long enough to be tucked inside trousers or a skirt
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