购物日

translate it word by word is 购物日, but we usually use the 购物狂欢节.

赶集, 购物节

Thanks!

I suppose you would like to say something like "Today is my shopping day." If that's the case, the direct translation will be 今天是我的購物日 But for native speakers, we tend to express the same concept as 我今天去逛街 ( I went shopping today) or 我今天逛了一整天的街 (I shopped for the whole day). We don't usually say "shopping day" in Chinese. Hope it helps.