compras is shopping...but deff can be used for "buy" or "purchase
Tienda
"Ellos(unneeded word) fueron de compras"
I go shopping, or, I go to shop.
shop (noun) = la tiendashop (verb) = hacer compras
compras
Vamos de compras. Vayamos de compras.
ir de compras
that means shopping in the paper goods store like ups or kinkos
"I'm going shopping with friends (all-female friends)."
ir de compras
torre de compras
"Fui de compras"