mother (honorific); your/his/her mother
Dated honorific term for someone else's mother, used in respectful or formal contexts. In modern Japanese, お母様 or お母さん are more common.
母君はご健在でいらっしゃいますか。
Is your mother in good health?
Compound of 母 (はは, 'mother') and 君 (ぎみ, honorific suffix). The exact historical derivation is uncertain, but the term follows a pattern of respectful address.