In the US, we generally call any room with a toilet a "bathroom" (or "restroom," which is a slightly more polite term). Even if there is no bath in the room, we still call it a bathroom. If there's a bath and also a toilet, it's a bathroom. If there's a toilet and no bath, it's a bathroom. If there's a bath and no toilet... I've never seen a room like that in the US, but it would probably still be called a bathroom.
As Michael says, the terms "full bathroom" and "half bathroom" can be used to distinguish a "complete" bathroom from a partial one -- but nobody uses these terms unless they're describing a house or apartment that they are planning to buy, rent, or sell.