乳光 Traditional form: 乳光 Pinyin (reading): rǔguāng Definitions: (mineralogy, physics) opalescence Characters: 乳 - breast, nipples; milk; to suckle 光 - light; bright, brilliant; only, merely Traditional characters: 乳 - breast, nipples; milk; to suckle 光 - light; bright, brilliant; only, merely