This phrasal verb means: "to completely accept an idea or belief and allow it to influence you".
You don't have to buy into the 'If you have a bigger house, you have a better life' theory.
This phrasal verb means: "to pay someone money or give them something that they want, in order to stop them causing trouble or threatening you".
In the US employers tried to buy off the unions by offering them higher and higher wage settlements.
This phrasal verb means: "to buy someone's share of a business or property that you previously owned together, so that you own all of it".
After the war, he bought out his Brother Bill's interest in the machine shop.
This phrasal verb means: "to quickly buy as much as you can of something, especially because there is not a lot available, or because you think you can make money from it".
People are buying up stocks of food in case the storm hits their area.
This phrasal verb means: "to buy a large amount of something, especially food or drink, because you may need a lot for a special occasion or it may become difficult to obtain".
We'd better buy in some more beer for the party.