tramp stamp
n.— «A tattoo on the lower back, when worn by young women, is occasionally called a “tramp stamp” or a “California license plate” in American slang.» —“Body Blogs” by Shweta Taneja Femina (India) Oct. 15, 2005. (source: Double-Tongued Dictionary)
Further reading
There are eight major planets, but more than a million minor ones, including asteroids. If you discover one, you get the honor of naming it. The Dictionary of Minor Planet Names includes minor planets named for rock bands, jazz musicians, poets, and...
One of the celestial bodies listed in The Dictionary of Minor Planet Names(Amazon) is called Sumaura. It’s the name of the oldest private elementary school in Kobe, Japan, and was suggested by the discoverer’s son. This is part of a...