What is the meaning and origin of the expression Show A Leg ?
When you tell someone to show a leg what you want him/her to do is to get out of bed. Instead of telling someone to wake up, you can tell him/her to show a leg or shake a leg. The idiom has its origins in the British navy. Before 1840, when the rules were fairly lax, sailors were sometimes permitted to take their wife/girlfriend along with them. While the sailors were expected to report for duty early in the morning, the wives/girlfriends were allowed to sleep on in the quarters down below. To ensure that a lazy sailor was not sleeping downstairs, an officer went down to check. Whenever he came across someone sleeping and wasn't really sure if it was a man or a woman under the covers, he used to shout show a leg. The person under the blanket had to stick his/her leg out. If the leg that emerged looked like that of a woman's, she was allowed to sleep, but if it looked like that of a man's, he was asked to get out of bed and report for duty. So originally when someone asked you to show a leg, all you had to do was to show him/her your leg.
Around 1840, when regulations in the navy were changed, women were no longer permitted to accompany the men. But the expression show a leg continued to be used. As time went on, this idiom which was mainly used in the navy became a part of everyday speech as well.
COURTESY : The Hindu (The National News-Paper) - India