• n. 先生；（用于姓名前）爵士；閣下；（中小學生對男教師的稱呼）先生；老師
• n. （蘇丹、德）西爾（人名）

來自古法語 sire,閣下，主，縮寫自拉丁語 senior,長者，老者，即 senior.后作為對男士的尊稱。

sir

sir: [13] In common with many other European terms of address for men (such as monsieur and se?or), sir goes back ultimately to Latin senior ‘older’ (source also of English senior). This was reduced in Vulgar Latin to *seior, which found its way into Old French as *sieire, later sire. English borrowed this as sire [13], which in weakly-stressed positions (prefixed to names, for instance) became sir.

Other titles based on senior that have found their way into English include French monsieur [15] (literally ‘my sire’), together with its plural messieurs [17], abbreviated to messrs [18]; French seigneur [16]; Spanish se?or [17]; and Italian signor [16]. Surly [16] is an alteration of an earlier sirly ‘lordly’, a derivative of sir.

The meaning ‘grumpy’ evolved via an intermediate ‘haughty’.
=> senator, senior, sire, surly

sir

c. 1300, title of honor of a knight or baronet (until 17c. also a title of priests), variant of sire, originally used only in unstressed position. Generalized as a respectful form of address by mid-14c.; used as a salutation at the beginning of letters from early 15c.

1. Sir Robert made his announcement after talks with the President.

在與總統會談之后，羅伯特爵士發表了聲明。

來自柯林斯例句

2. Sir Denis took one look and sent it back.

丹尼斯爵士看了一眼就把它送了回去。

來自柯林斯例句

3. Sir Geoffrey had no personal animosity towards the Prime Minister.

杰弗里爵士對首相并無私人恩怨。

來自柯林斯例句

4. "We need proof, sir." Another pause. Then, "Very well."

“我們需要證據，先生。”又是一個短暫停頓。然后，“那好吧。”

來自柯林斯例句

5. Ben Brantley's article on Sir Ian McKellen rekindled many memories.

本·布蘭特利的那篇關于伊恩·麥凱倫爵士的文章喚起了許多記憶。

來自柯林斯例句