A URL shortener can be described as an URL shortener... it's similar to the term "link shrinker... A compressor of links... A URL condenser. I'm sure that's everything included. There are a variety of ways to say a similar thing. The idea is that we'd like to take something long and ugly, and then make it cute and short. To simplify things I'll stick to the word URL shortener starting today and until the day I pass away.