Archaic respectful term for one's own or someone else's mother, used in classical Japanese or historical settings. Not used in modern everyday speech.
古文書には「母の命」と記され、敬意を表している。
In old documents, '母の命' is written, showing respect.
The term combines 母 (mother) with the honorific suffix 命 (みこと), which was historically used for deities and high-ranking persons. The exact origin is uncertain, but it reflects an archaic pattern of respectful address.