Which fixture does NOT typically have a P-trap?

A water closet, commonly known as a toilet, does not typically have a P-trap. Instead, it is designed with a built-in trapway that serves a similar purpose. The trapway is integral to the toilet's construction and prevents sewer gases from entering the building, functioning as a trap by holding a small amount of water at the bend.

In contrast, kitchen sinks, lavatories, and floor drains all require external P-traps to effectively block sewer gases from escaping into the living space. These fixtures utilize a separate P-trap assembly to maintain a water seal, which is critical for proper drainage and odor control. Therefore, understanding the specific plumbing requirements of different fixtures clarifies why a toilet operates differently compared to sinks and drains regarding trap installation.