Elcrystal, welcome to the forum.
I've been shopping well over 10 years, and every single time I accept a "new to me" shop, I run into jargon and need explanation of what they mean.
I recall my first "big box" store shop; I didn't know what "front line" was, I didn't know several other things, all jargon I wasn't familiar with. I asked the scheduler, and she nastily wrote back she didn't have time to answer my questions; I cancelled the shop (200 mile round trip drive with an excellent chance of screwing up the shop? I think not, thank you!).
To make it worse, different MSCs use differing words for exactly the same thing.
Glad you asked, and don't hesitate to ask again.