古音

gǔyīn
  1. ancient (esp. pre-Qin) pronunciation of a Chinese character
  2. classical speech sounds

CEDICT

  1. (phonology) ancient pronunciation of Chinese characters
  2. ancient music
  3. ancient pronunciation of Chinese characters

Wiktionary

古代的字音。多指先秦之音，以《詩經》為主，其他如《楚辭》、先秦諸子中的韻語，皆為研究古音的資料。

重編國語辭典

Entry Composition

1 古 gǔ
  1. ancient
  2. old
  3. paleo-
2 音 yīn
  1. sound
  2. noise
  3. note (of musical scale)
  4. tone
  5. news
  6. syllable
  7. reading (phonetic value of a character)