also: しん
Archaic term for a servant or vassal in historical contexts.
In old documents, 臣 referred to a person who served a lord.
Omi (hereditary title)
Only with reading おみ
Historical hereditary title; originally one of the two highest, later demoted to sixth of eight under the 八色の姓 system. Reading is おみ.
See also: 八色の姓
Only with reading しん
Humble first-person pronoun used by a servant when addressing their master. Reading is しん. Extremely rare and archaic.
Under the eight kabane system, the Omi rank was lowered to the sixth position.
"I shall receive your command," the retainer said to his lord.
臣下 is a slightly more common classical term for a subject or retainer, largely interchangeable with the archaic 臣.
連（むらじ）and 臣（おみ）are both hereditary kabane titles from the Yakusa no Kabane system, but 臣 originally ranked higher and was reserved for court nobility, while 連 was tied to military and ritual clans.
Standard kanji form for the historical title and archaic retainer sense.
Reading しん is used for the humble first-person pronoun in archaic servant speech.
The kanji 臣 originally depicted an eye looking down, symbolizing a servant or subject. The reading おみ is native Japanese, while しん is the Sino-Japanese reading.