A more thorough explanation:

Definition: Locked in is an adjective used to describe a situation where a person is unable to sell appreciated securities and realize the gain because of liability for capital gains taxes. It can also refer to a price, rate, or other value that remains the same for a given period.

Example 1: My accountant advised me not to sell the stock because I am locked in. This means that the person cannot sell their appreciated securities without incurring a large tax liability. They are "locked in" to holding onto the securities until a later time when the tax liability may be lower.

Example 2: The 7% mortgage rate is locked in for 30 days. This means that the interest rate on the mortgage will remain the same for the next 30 days, regardless of any changes in the market or economy.

Example 3: A person may also be "locked in" to a contract or agreement, meaning they are bound by its terms and cannot easily get out of it. For example, a cell phone contract may have a "locked in" period of two years, during which the person cannot cancel the contract without incurring a penalty.

Overall, the term "locked in" refers to a situation where a person or value is unable to change or move for a given period of time.