大后

Shift from Old Japanese 大后 (opoki₁saki₁), modern ōkisaki.

Equivalent to 大 (ō-, “great”) +‎ 后 (kisai, “wife of male aristocrat”, sound shift from earlier kisaki).

大(おお)后(きさい) • (ōkisai) ^{←おほきさい (ofokisai)?}

1. (archaic) an empress (of ancient or early medieval Japan)
   • c. 1001–1014, Murasaki Shikibu, Genji Monogatari (Wakana, part 1)

     ...御(おほん)交(ま)じらひの程(ほど)も心(こころ)細(ぼそ)げにて、大(おほ)后(きさい)の内侍(ないしのかみ)を参(まゐ)らせたてまつり給(たま)ひて...

     ...ōnmajirai no hodo mo kokorobosoge nite, ōkisai no naishi no kami o mairase tatematsuri-tamaite...

     (please add an English translation of this example)

• 太(おお)后(きさい) (ōkisai, “empress dowager”)

• 皇后(こうごう) (kōgō)

Likely a Baekje compound; if so, possibly from 鞬 (*k(j)ə-n, “big, great”) +‎ 於陸 (*oLuk, “queen”).

Doublet of Old Japanese 大后 (kon'oruku).

• (Tokyo) コニオ​ルク [kòníóꜜrùkù] (Nakadaka – [3])[1]
• IPA^(key): [ko̞ɲ̟io̞ɾɯ̟ᵝkɯ̟ᵝ]

大后(コニオルク) • (konioruku) 

1. (historical) a queen (of Baekje)
   • 1274–1301, Shaku Nihongi (volume 17)

     大后（コムヲルク、コヲルク、コ尓ヲルク）

     Queen: [variously read as] komuoruku, kooruku, [and] konioruku

     [Note: some later manuscripts omit completely these phonetic readings, or swap ル and ク for this particular reading as koniokuru as a scribal error.]

From 大 (opo-, “great”) +‎ 后 (ki₁saki₁, “wife of male aristocrat”).

大后 (opoki₁saki₁) (kana おほきさき)

1. an empress (of ancient or early medieval Japan)
   • 711–712, Kojiki, middle volume (Emperor Jimmu):

     然更求_二爲_レ大_-后之美人_一時...

     But when [he] sought a beautiful maiden worthy of being Empress...

• 太后 (opoki₁saki₁, “empress dowager”)

• Japanese: 大后 (ōkisaki → ōkisai)

Likely derived from a Baekje compound; if so, possibly 鞬 (*k(j)ə-n, “big, great”) +‎ 於陸 (*oLuk, “queen”).

大后 (ko(n')oroku) (kana コンオルク)

1. a queen (of Baekje)
   • 720, Nihon Shoki, Emperor Yūryaku (twentieth year of reign [c. 476 CE] in winter; Maeda-bon glosses):

     百濟記云_下：蓋鹵王乙卯年冬。狛大軍來、攻_レ大_-城七日七夜、王城降陷、遂失_二尉禮國_一、王及大后、王子等、皆沒_二敵手_一上。

     The Baekje records read: Gaero was king in the winter year of the Wood Rabbit [475 CE]. An army from Köma (Goryeo) came, attacked the castle for seven days and seven nights; the king’s castle fell and was captured, finally Wirye was lost; the king, queen, and princes all fell into enemy hands.

• Japanese: 大后 (kon'oroku), in modern Japanese dictionaries

• “コンオルク 【大后】”, in 日本国語大辞典 (Nihon Kokugo Daijiten, “Nihon Kokugo Daijiten”) ‎ (in Japanese), 2nd edition, Tōkyō: Shogakukan, 2000, released online 2007, →ISBN, concise edition entry available here (Note: Dialectal meanings, etymological theories, pronunciation including modern, dialectal, and historical information, Jōdai Tokushu Kanazukai, historical dictionaries containing this word, and the kanji spellings in those dictionaries have been omitted.)