If you’ve ever seen “WC” on a bathroom door and paused in confusion, you’re not alone. Short for “water closet,” WC refers to a room with a toilet—often with a sink. Though common on signs around the world, it still raises eyebrows among English speakers used to “restroom,” “bathroom,” or “washroom.”

Historically, a water closet was a small, private room for using the toilet, separate from rooms used for bathing or freshening up. As plumbing advanced in the 19th century, these “closets” became part of wealthier homes before evolving into today’s modern bathrooms.

Terminology varies by region. Canadians prefer “washroom,” Americans lean toward “bathroom” or “restroom,” and Brits often say “loo.” On TikTok and Reddit, debates have sparked over which term makes the most sense—none are truly literal.

So why does “WC” persist? Because it’s a short, recognizable label that helps travelers from all over the world find the facilities—no translation needed.

Next time you spot “WC,” smile—you’re in on the secret (and maybe the history too).