a sit down is taking a break?

I haven't heard the phrase before, no. oo

^^ It's more like... chilling out. You've had a hard day, been on your feet all day, time for a cup of tea and a nice sit down! ^^

I knew what it was!

Ah yes, but do you use the term? XD

sometimes, mostly with Duckie, since he uses a lot of Britishisms

HAHA I knew there was a reason I liked him!

XD

When I hear nice sit down I think of a nice sit down restaurant aka eating something better than fast food while on a road trip.

^^ that would make sense! but it's basically just sitting down to take the weight off your feet! relaxing for a minute, or the night if you've just got home!