Archaic honorific second-person plural pronoun, used primarily by men in classical or historical contexts. Not used in modern Japanese; equivalent to modern あなた方 or 皆様.
In classical literature, one can find scenes where a lord addresses his retainers as 'keira'.
Composed of 卿 (kei, 'lord' or honorific second-person) and 等 (ra, plural suffix). The exact historical derivation is uncertain, but it follows a classical pattern of forming respectful plural pronouns.