What is the meaning of "orpiment" in the word "orpiment"?

I. "Orpiment" here means: yellow mineral, used as a pigment. Ancient people wrote on yellow paper, and when they made a mistake, they rewrote it after smearing it with orpiment.

The meaning of the term "信口雌黄" is: to speak out of turn or to comment without regard to the facts.

Three, source: Jin-Sun Sheng "Jin Yang Qiu": "Wang Yan, word Yifu, can speak, in the intention of the uneasy, always easier, when the number of the mouth in the orpiment."

Vernacular interpretation:

Wang Yan, the word Yifu, articulate, feeling that others speak of what is inappropriate in the doctrine of the scriptures, immediately have to refute the change, (we see that Wang Yan so like to change the words of others) so they gave him a nickname -- "mouth in the orpiment". "Orpiment in the Mouth".

I. Near Synonyms:

Delusional Orpiment [ wàng xià cí huáng ]?

Definition: not according to the objective standard, according to their own will, change the text, nonsense comments. Orpiment: the paint used in the olden days to correct the text.

Origin: Northern Qi - Yan Zhiwei "Yan's family training - reluctant to learn": "proofreading books; also how easy? Since Yang Xiong, Liu Xiang; Fang called this job ear. The books of the world have not yet been read; they shall not be written in a presumptuous manner."

Translation: How easy is it to proofread books? Only people like Yang Xiong and Liu Xiang were qualified to serve in this position. Before reading all the books under the sun, they were not able to change the text or add comments indiscriminately.

II. Antonyms:

Letters and signs? [ xìn ér yǒu zhēng ]?

Interpretation:信：确实；征：征验，证据。 Reliable and with evidence.

Source: Spring and Autumn Period - Zuo Qiu Ming, "Zuo Zhuan - Zhaogong VIII": "The words of a gentleman are reliable and have evidence."

Translation: what a gentleman says must be supported by reliable evidence.