Apparently, as soon as a gentleman has forgotten to zip his pants, in the US they remind him thusly

Your fly is open lists the noun fly meaning: 20. a sexpedition of product sewn along one edge of a garment opening for concealing butlots, zippers, or other fasteners.

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But in the UK a trouser zipper is also called flies,

Your flies are open

Huffington Post, edition UK, has actually the following title in their light-hearted write-up handling the social faux pas:

“Your Flies Are Undone!”

The post then mentions a British euphemism that was commonly heard before WWII that signalled the gentleguy to fasten the butloads on his trousers.

“There’s a star in the East”

The British writer, and also The Times journalist Philip Howard, seems to confirm the validity of this expression.


Are the terms "fly" and "flies" interchangeable? Are Americans and also British mainly mindful of the 2 expressions?

What is the origin of "fly" and also "flies" (i.e. men"s zippers)? colloquialisms euphemisms
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edited Sep 6 "17 at 8:57
Mari-Lou A
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In Britain the term was constantly flies, as in your flies are undone.

The just world I have heard refer to a fly in this regard are Americans. However before the 2 expressions deserve to sound the exact same, and also the distinction not be obvious, considering that an Amerihave the right to could say your fly"s undone which sounds a little favor the British term flies.

I think the British expression goes earlier to the days prior to zips came in (1960s?) once they were always butloads - for this reason arguing a plural rendering, flies being short for fly buttons.

I"m not old enough to remember anyone saying "there"s a star in the east", the usual modern euphemism is to tell the unfortunate he is "flying low".

I think Americans had actually zips prior to we did, the British male for a time considering them as well effeminate, prior to they caught on. ("Real males do not wear zips in their clothing" may have been the sentiment.)

The OED entry with examples adheres to. It draws no specific difference between British and also Amerihave the right to intake, yet from the examples it is sensibly clear which ones are which.

Something attached by the edge. Cf. flap n. 4.

a. A spilgrimage or lap on a garment, to contain or cover the button-holes; thus somepoint offered to cover or affix (watch quot. 1884). spec. (generally in pl.) the piece of cloth that hides the fastening at the front of a pair of trousers; additionally, the fastening itself.

1844 Queen"s Regulations & Orders Army 154 Open in front, through a Fly and also Five Buttons.

1884 E. H. Knight Pract. Dict. Mech. IV. 351/1 Fly, the fore flap of a bootee. A strip of leather which overwraps the front vamp and also receives the strings or other fastening.

1941 I. Baird He rides Sky 234 A pair of tennis shorts via zipper fly.

1942 E. Paul Narrowhead Street i. 6 The professor..turned toward the pissoir, unbuttoning his fly en path.

1952 ‘Vigilans’ Chamber of Horrors 27 The words button one"s fly are offensive only to the prurient.

1953 M. Dickens No More Meadows i. 49 Champ, your flies are undone aobtain. That boy! He"ll be arrested yet.

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1959 R. Fuller Ruined Boys ii. viii. 128 ‘Your flies are undone,’ sassist Matley primly.