A common term used in ComputerScience to indicate that a certain program, method or option is no longer in use, or has been replaced by another.

The dictionary tends to suggest that deprecation is used like depreciation, but the word correctly means "To express disapproval of"; in computer science the implication is that the feature is still here, but it's being removed and might stop working in future.

JargonFile:deprecated defines 'deprecated' as:

Said of a program or feature that is considered obsolescent and in the process of being phased out, usually in favour of a specified replacement. Deprecated features can, unfortunately, linger on for many years. This term appears with distressing frequency in standards documents when the committees writing the documents realise that large amounts of extant (and presumably happily working) code depend on the feature(s) that have passed out of favour.