What is the ruling of Islamic law regarding saying "Dead Mother" or "Dead Father" in a state of anger?

Slandering a Muslim is forbidden by the consensus of the Ummah, and its perpetrator is a fasiq (transgressor). The prohibition and deterrence are further emphasized in the case of the deceased, as their sanctity remains, and they may not find anyone to protect their honor and defend them. The Prophet, peace and blessings be upon him, forbade slandering the dead, saying: "Do not revile the dead, for they have gone on to what they have sent forth." The statement of someone saying "the dead father of so-and-so" or "the dead mother of so-and-so," if it refers to Muslim individuals, is one of the grave sins that necessitates repentance, whether it is said in a state of contentment or anger. If the intention is not directed at individuals, such as saying "the dead mother of the school," it is considered foul language, and a believer is not one who slanders, curses, speaks obscenely, or is vulgar. A Muslim must guard their tongue and restrain it from obscenity and foul speech.