TVLINE.COM – Who’s ready for another vocabulary lesson? (Yes, we realize that Christmas is not a school day, but we think you’ll really like this one.)

Last week, TVLine presented you with four terms every Shadowhunters fan will need to know before the series’ Jan. 12 premiere (ABC Family/Freeform, 9/8c), and we’re back again — along with stars Katherine McNamara, Dominic Sherwood, Matthew Daddario, Alberto Rosende and author Cassandra Clare — for another exclusive behind-the-scenes vocab lesson.
In addition to explaining key terminology, the video also gives us a look at Jace and Alec — they’re “parabatai,” which you’ll understand after watching — in action, and it’s kind of epic.