The phrase "to buy a jar" means to purchase a container with a lid that is typically used for holding things like food or other small items. Full definition
I just bought a jar of pumpkin seed butter at my local health food store too! (golubkakitchen.com)
The recipe calls for a store bought jar of vegan marshmallow fluff, but you can just use the recipe in number 17 instead. (eluxemagazine.com)
This sauce is good on homemade pizza or as a pasta topping, and it'll make you want to never buy a jar of sauce off the shelf again. (homemadeupgrade.com)