It all started as a reminder about which relatives the Catholic Church prohibited you from marrying.

ETYMOLOGY
If our hands turn into a mess of smeared dirt when gardening, how come we have green thumbs? Why not green fingers?
‘Coronavirus’ is named for how it looks under a microscope, but that’s not the only way to name a virus or disease.
The name for the classic St. Patrick’s Day tricksters comes from a very weird ancient Roman festival called Lupercalia.
The Chicago-based women name about 200 generic drugs per year, and the naming process is very scientific … sometimes.
The game of hopscotch has nothing to do with little kids skipping over glasses of Johnnie Walker. What is going on?
It might have something to do with baseball in the late 1800s.
They're not completely interchangeable.
Chances are, you use some of these expressions in conversation frequently—maybe even every day. But where do they come from, anyway?
An incredible number of lines from William Shakespeare's plays have become so ingrained in modern vernacular that we no longer recognize them as lines from plays at all.
Most of its neighborhood names aren’t in English—and they all have colorful stories.
Bacons have shaped American cities, influenced presidents, and given us an enduring parlor game.
The story behind one of today's big buzzwords goes all the way back to the secret slang of early 19th century criminals.
Like proud parents, scientists often give their discoveries the biggest, most impressive names they can think of.
Here are 15 etymologies to answer the questions of future English speakers. Because the future is already here.
Many of Philadelphia’s suburbs have been around since before the American Revolution, and some are even as old as Pennsylvania itself. But how did they get their names?