I can't blame you for that... I've tended to do the same thing, searching Google and forums for my answers instead of turning to Hamer & Hamer first. I'm getting better at remembering that it's there and what it's for.
I'm with Stephen - semantics. I use the term biscuit firing for any firing before glazing and bisqueware for the stuff I might buy from someone like Potclays to just glaze myself ie is made for the particular purpose of commercial selling for people who perhaps cannot throw items etc and would like to make presents that are unique for their friends and family or to practice upon. I use leatherhard for anything that has dried and is ready for firing. But it is very personal. Like most things in art, don't get too caught up in these things. Use the terms that you feel comfortable with e.g the ones you were first taught or heard x