雄黄

/juːwau/ → /juːwɔː/ → /juːoː/

From Middle Chinese compound 雄黃 / 雄黄 (hjuwng hwang, literally “male + yellow”), indicating the mineral realgar, in contrast to 雌黄 (tsiɛ hwang, literally “female + yellow”), indicating the mineral orpiment.

Due to similarities between the two minerals, when the term was borrowed into Japanese, the meaning changed from realgar to orpiment.

• (Tokyo) ゆうおー [yùúóó] (Heiban – [0])^[1]
• IPA^(key): [jɯ̟ːo̞ː]

雄(ゆう)黄(おう) • (yūō) ^{←ゆうわう (yuuwau)?}

1. orpiment, an arsenic sulfide mineral

This is the most common reading for this kanji compound.

• 石黄(せきおう) (sekiō)
• 雌黄(しおう) (shiō) (rare)

/wowau/ → /owɔː/ → /ooː/

Compound of 雄 (o, “male”, from Old Japanese) +‎ 黄 (ō, “yellow”, from Middle Chinese).

• (Tokyo) おおー [òóó] (Heiban – [0])
• IPA^(key): [o̞o̞ː]

雄(お)黄(おう) • (oō) ^{←をわう (wowau)?}

1. (rare, possibly obsolete) orpiment, an arsenic sulfide mineral

• 石黄(せきおう) (sekiō)
• 雌黄(しおう) (shiō) (rare)

From Old Japanese. Compound of 黄 (ki, “yellow”) +‎ 丹 (ni, “earth, reddish earth”). The kanji are ateji, borrowed from the Chinese term.

Cognate and homophone of 雌黄 (kini, “orpiment”). Only differentiated by spelling.

• IPA^(key): [kʲiɲ̟i]

雄黄(きに) • (kini) 

1. (rare, possibly obsolete) realgar, an arsenic sulfide mineral

• 鶏冠石(けいかんせき) (keikanseki) (more common)