What do you consider a "half bath"?

The real estate folks prefer to call a bathroom with shower a "3/4 bath". And when there's more than one fractional bathroom in the house, they'll usually count the extras as 1 (so that a house with one full bathroom, two with showers, and an extra toilet/sink would probably be called "3-1/2 baths" rather than 3).

And isn't it good to know that Wikipedia has an article called "Bathroom"?

Terminology in the United States

In the United States, bathrooms are generally categorized as master bathroom, containing a shower and a tub that is adjoining to a master bedroom, a "full bathroom" (or "full bath"), containing four plumbing fixtures: bathtub, shower, toilet, and sink; "half (1/2) bath" (or "powder room") containing just a toilet and sink; and "3/4 bath" containing toilet, sink, and shower, although the terms vary from market to market. In some U.S. markets, a toilet, sink, and shower are considered a "full bath". This lack of a single, universal definition commonly results in discrepancies between advertised and actual number of baths in real estate listings. An additional complication is that there are currently two ways of notating the number of bathrooms in a dwelling. One method is to count a half bathroom as ".5" and then add this to the number of full bathrooms (e.g., "2.5" baths would mean 2 full baths and 1 half bath). The other, newer method is to put the number of full bathrooms to the left side of the decimal point and to put the number of half bathrooms to the right of the decimal point (e.g., "2.1" would mean 2 full baths and 1 half bath; "3.2" would mean 3 full baths and 2 half baths).

Bathroom - Wikipedia, the free encyclopedia