Deprecation

In several fields, deprecation is the discouragement of use of some feature, design or practice; typically because it has been superseded or is no longer considered efficient, or safe – but without completely removing it or prohibiting its use.

In general English usage, the infinitive "to " means "to express disapproval of (something)". It derives from the Latin verb deprecare, meaning "to ward off (a disaster) by prayer". In current usage, for one to state that a feature is deprecated is merely a recommendation against using it. It is still possible to produce a program or product without heeding the deprecation.

While a deprecated software feature remains in the software, its use may raise warning messages recommending alternative practices; deprecated status may also indicate the feature will be removed in the future. Features are deprecated rather than immediately removed, to provide backward compatibility and give programmers time to bring affected code into compliance with the new standard.

Among the most common reasons for deprecation are:

An example in hardware design is omission of pull-up resistors on unused inputs to a logic gate. This practice may have been acceptable in the past, but becomes deprecated because faster clock speeds are likely to induce more transient noise on input lines, causing hardware glitches or malfunctions.

A building code example is the use of ungrounded ("2-prong") electrical receptacles. Over time, these older devices were deprecated in favor of the safer grounded ("3-prong") receptacles. The obsolete ungrounded receptacles were still permitted by "grandfathering" in existing electrical wiring, but became prohibited from new installations. Ungrounded receptacles are still available for legal purchase, but are intended solely for repairs to existing older electrical installations.

In writing and editing, usage of a word may be deprecated because it is ambiguous, confusing, or offensive to some readers. For example, the words and inflammable may be misinterpreted because they have auto-antonymic or self-contradictory meanings; writing style guides often recommend substituting other words that are clearly understood and unambiguous. Some word usages that have acquired different connotations over time, such as gay or colored, may be deprecated as obsolete in formal writing.

...
Wikipedia