IPA: //ˌdiːˈkɒnsəˌkreɪt//
KK: /diˈkɒnsɪˌkreɪt/
To make a place of worship, like a church or temple, no longer sacred or holy.
The community decided to deconsecrate the old church after it was no longer in use.
Past: deconsecrated
Past Participle: deconsecrated
Deconsecrate is formed from "de-" (meaning down or away from) and "consecrate" (from Latin "consecratus", meaning to make sacred). The word means to remove the sacred status from something, effectively taking it away from its consecrated state.
Think of 'taking away' ('de-') the 'sacredness' ('consecrate') from something — that's what deconsecrate means.