As someone who transplanted from the US to the UK about nine months ago, there have been some things to which I've had to adjust. I figured that the vocabulary differences wouldn't be an issue... after all, half of my extended family lives in the UK, and everyone already knows about basic things like sweater/jumper, truck/lorry, crisps/chips, sidewalk/pavement etc.
What I didn't know was that in the UK they often use different words for various fabrics, notions, or sewing terms than are used in America. So for all the sewists out there looking to hop the pond in either direction, here's what I've run across so far:
Cheesecloth = Muslin
Muslin = Calico
Burlap = Hessian
Mock-up = Toile
Seam-ripper = Unpicker
Stitch Witchery = Bondaweb
To baste something = To tack something
Serger = Overlocker
Snaps = Poppers
If anyone has any more words to add to the list, please let me know! I'd love to have a comprehensive list going!
I'm also trying to get better at working with the metric system... having 1 or 1.5 cm seam allowances have at least begun to seem somewhat natural, though it's a work in progress!