Buy may be used as a transitive verb. Bought, buying, buys
Buy may mean to acquire in exchange for money or its equivalent, to purchase. "They were able to Buy supplies at a good price."
Buy may mean to be capable of purchasing. "Money will not Buy some of the better things in life."
Buy may mean to acquire by exchange, trade or sacrifice. "The Israelis were asked to Buy peace by giving up land."
Buy may mean to bribe. "He tried to Buy the judge."
[Informal] Buy may mean to accept the truth or feasibility of. "The cops did not Buy my
alibi."
Buy may be an intransitive verb. "Wheat is what I came to Buy."
Buy may be used as a noun.
Buy may be used to refer to something bought or for sale; purchase. "He made a major Buy of art at the auction."
Buy may mean an act of purchasing. "The police arrested him for making a drug Buy."
Buy may mean something that is underpriced; a bargain. "For the price he was asking, the car was a Buy."
Buy may be used as part of a phrasal verb.
Buy Into may mean to acquire an interest in. "They wanted him to Buy Into their business venture."
[Informal] Buy Into may mean to believe in, especially wholeheartedly. "They wanted me to Buy Into the idea that they could deliver computer parts in quantity."
Buy Off may mean to bribe (an official, for example) in order to secure improper cooperation or gain exemption from a regulation or legal consequence. "It is illegal to import the drug, but they were able to Buy Off the border guard."
Buy Out may mean to purchase the entire stock, business rights, or interests of. "He was able to Buy Out the bankrupt company at a very good price."
Buy Up may mean to purchase all that is available of. "If they Buy Up all the spare parts for my generator, I am in trouble."