A more thorough explanation:

fix, n.

1. A dose of an illegal drug. For example, "He needed to buy a fix."
2. A navigational reading.

fix, vb.

1. To announce an exchange price, interest rate, etc. For example, "Interest was fixed at 6%."
2. To establish a person's liability or responsibility. For example, "You cannot fix liability on the defendant without evidence."
3. To agree with another to establish a price for goods or services, often illegally. For example, "Representatives of Acme and Widget secretly met to fix prices for their companies' products." This is also known as price-fixing.
4. To influence an action or outcome, especially a sports event, by improper or illegal means. For example, "After losing the election, the challenger claimed that the incumbent had fixed the election."

The term "fix" can have different meanings depending on the context. It can refer to a dose of an illegal drug or a navigational reading. It can also mean to establish a price for goods or services, announce an exchange rate, or influence an outcome by improper means.

For example, if someone says they need to buy a fix, they are referring to a dose of an illegal drug. If someone announces that interest rates are fixed at 6%, they are stating the established rate. If two companies secretly agree to fix prices for their products, they are engaging in illegal price-fixing. If someone claims that a sports event was fixed, they are alleging that the outcome was influenced by improper means.