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definitions

shirt

[shurt]
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noun

a long- or short-sleeved garment for the upper part of the body, usually lightweight and having a collar and a front opening.
an undergarment of cotton, or other material, for the upper part of the body.
a shirtwaist.
a nightshirt.

Idioms

    in one's shirt sleeves, without a coat: It was so hot that they worked in their shirt sleeves.Also in one's shirt-sleeves.
    keep one's shirt on, Informal. to refrain from becoming angry or impatient; remain calm: Tell him to keep his shirt on until we're ready.
    lose one's shirt, Informal. to lose all that one possesses; suffer a severe financial reverse: He lost his shirt in the stock market.

Origin of shirt

before 1150; Middle English schirte, Old English scyrte; cognate with German Schürze, Dutch schort apron, Old Norse skyrta skirt
Related formsshirt·less, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for in one's shirt-sleeves

shirt

noun

a garment worn on the upper part of the body, esp by men, usually of light material and typically having a collar and sleeves and buttoning up the front
short for nightshirt, undershirt
keep your shirt on informal refrain from losing your temper (often used as an exhortation to another)
put one's shirt on informal to bet all one has on (a horse, etc)
lose one's shirt on informal to lose all one has on (a horse, etc)

Word Origin for shirt

Old English scyrte; related to Old English sceort short, Old Norse skyrta skirt, Middle High German schurz apron
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Word Origin and History for in one's shirt-sleeves

shirt

n.

Old English scyrte "skirt, tunic," from Proto-Germanic *skurtjon "a short garment" (cf. Old Norse skyrta, Swedish skjorta "skirt, kirtle;" Middle Dutch scorte, Dutch schort "apron;" Middle High German schurz, German Schurz "apron"), related to Old English scort, sceort "short," from PIE *(s)ker- (1) "to cut" (see shear (v.)).

Formerly of the chief garment worn by both sexes, but in modern use long only of that for men; in reference to women's tops, reintroduced 1896. Bloody shirt, exposed as a symbol of outrage, is attested from 1580s. To give (someone) the shirt off one's back is from 1771. To lose one's shirt "suffer total financial loss" is from 1935. To keep one's shirt on "be patient" (1904) is from the notion of (not) stripping down for a fight.

Online Etymology Dictionary, © 2010 Douglas Harper
Idioms and Phrases with in one's shirt-sleeves

shirt

see give the shirt off one's back; hair shirt; keep one's shirt on; lose one's shirt; stuffed shirt.

The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.