You have to watch out as those terms are tossed around and often hardly mean a thing.
I know I use to sell a paint called a "Acrylic Urethane enamel". It had a kissing cousin made from the very same toners and re-labeled (no one was suppose to know) and sold as a value line. It was called a "Urethane enamel". LOL, you are dealing with a "value line" and it's anyones guess what it is.