Highness is the polite word you use when you speak to or about a royal person such as a prince or a princess. You almost never say it on its own.

Highness is the polite word you use when you speak to or about a royal person such as a prince or a princessHighness是你對王室成員（像王子或公主）說話、或談到他們時用的禮貌用字。You almost never say it on its own你幾乎不會單獨說這個字。

To their face you say Your Highness; when you talk about them you say His Highness or Her Highness (and Their Highness for more than one). It is palace language: very polite, rather stiff, and not for the street.

To their face you say Your Highness對著本人你會說 Your Highness殿下; when you talk about them you say His Highness or Her Highness談到對方時則說 His Highness他殿下或 Her Highness她殿下 (and Their Highness for more than one)（不只一位就說 Their Highness）。It is palace language這是宮廷用語: very polite, rather stiff非常禮貌、也相當拘謹, and not for the street不是街頭會用的說法。

You do not use it for a president, a boss, or a teacher — those have other polite forms. It is high + -ness, “the state of being high.” English also copied this way of naming a royal person from the same idea in Italian altezza, itself from Latin built on a word for high.

You do not use it for a president, a boss, or a teacher你不會用它稱呼總統、老闆或老師 — those have other polite forms這些人有各自的禮貌稱呼。It is high + -ness它是 high高加上 -ness, “the state of being high.”意思是「高的狀態」。English also copied this way of naming a royal person英文也是照這個方式來稱呼王室成員的, from the same idea in Italian altezza這概念跟義大利文的 altezza一樣, itself from Latin built on a word for high而 altezza又源自拉丁文一個意思是「高」的字。

Friends may say “Yes, Your Highness” as a joke when someone is acting too grand; that is play, not real court talk.

Friends may say “Yes, Your Highness” as a joke朋友之間可能會開玩笑說「Yes, Your Highness遵命，殿下」 when someone is acting too grand用來取笑某人擺架子, that is play, not real court talk這只是玩笑，不是真正的宮廷用語。