Also found in: Dictionary, Thesaurus, Medical, Encyclopedia.
What one is said to be "wearing" while completely naked. Alludes to the fact that one is born without clothing. I have a recurring nightmare where I'm walking through school in my birthday suit. As kids, we had no problem going swimming together in our birthday suits.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
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.
The American Heritage® Dictionary of Idioms by Christine Ammer. Copyright © 2003, 1997 by The Christine Ammer 1992 Trust. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Wearing no clothes. People said to be in their birthday suit are as naked as the day they were born.
Endangered Phrases by Steven D. Price Copyright © 2011 by Steven D. Price