Meaning
The official declaration that a software feature, API endpoint, or library is outdated, discouraged from use, and slated for future removal.
Three examples from work
API lifecycle
LeadWe must announce the deprecation of API v1 six months before shutting it down.
DevRelI will send migration guides and email notifications to all registered developers.
Compiler warning
DevThe build log is filled with deprecation warnings for the old crypto library.
LeadLog a tech debt ticket to upgrade to the new TLS module before the next release.
Contract review
ClientWill our existing webhooks break when you deprecate legacy event types?
PMNo, deprecated events will continue functioning until the end of next year.
Verbal form is 'deprecate' ('we deprecated v1'). Deprecation gives clients a fair grace period to migrate before a breaking removal occurs.