birthday suit

American  

noun

1. bare skin; nakedness.

   They were sunbathing in their birthday suits.

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birthday suit British  

noun

1. informal a state of total nakedness, as at birth

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birthday suit Cultural  

1. To be “in one's birthday suit” is to be completely naked (as people are at birth).

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birthday suit Idioms  

1. Nakedness, as in The doorbell rang, and here I was in my birthday suit. In 18th-century Britain this term originally referred to the clothes one wore on the king's birthday. Later it was jocularly transferred to bare skin, alluding to the condition of a newborn baby.

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Etymology

Origin of birthday suit

First recorded in 1745–55

Example Sentences

Dancers strip down to pasties and G-strings, or to their birthday suit, with some strategic covering.

From Los Angeles Times

"In nothing but my birthday suit today..." she wrote in the caption of the post.

From Fox News

Nudism first caught on in the United States 90 years ago, brought over by German immigrants who believed the best way to commune with nature was in one’s birthday suit.

From Seattle Times

George Knightley, her eventual love interest, first appears in his birthday suit.

From Washington Times

In related headlines, a traveler passing through Moscow’s Domodedovo Airport caused quite the commotion last year when he attempted to board a flight in his birthday suit.

From Fox News