Poetic and archaic term used to refer to one's lord or master, often in classical literature or waka poetry.
I humbly speak thus before my lord.
Poetic, familiar, and polite term of address used toward a beloved or respected person, often in classical or literary contexts.
My dear, how are you faring?
Standard kanji spelling for this classical poetic expression.
Kana spelling sometimes used for clarity or in modern contexts.
From 我が (my) + 君 (lord, you). The exact historical derivation is uncertain, but it is a classical poetic expression.