英 [sɜː(r)] 美 [sɜːr]
n. 先生，长官（尤指对上级的尊称）；老师（学生对男教师的称呼）；先生，阁下（正式或商业信函开头的称呼）（Dear Sir）；爵士（用于爵士或准男爵名字之前）（Sir）；<美，非正式>决不，的确（no/yes sir）（同 siree）
【名】 （苏丹、德）西尔（人名）
复数sirs
sir /sɜː/ CET4 TEM4
称呼名词 People sometimes say sir as a polite way of addressing a man whose name they do not know, or an older man. For example, a shop assistant might address a male customer as sir. 先生 (对男性的客气称呼)
Excuse me sir, but would you mind telling me what sort of car that is?
对不起，先生，您能告诉我那是什么样的汽车吗？
头衔名词 Sir is the title used in front of the name of a knight or baronet. (爵士或从男爵名字前的头衔) 爵士
She introduced me to Sir Tobias and Lady Clarke.
她把我介绍给托拜厄斯爵士和克拉克夫人。
习惯表达 You use the expression Dear Sir at the beginning of a formal letter or a business letter when you are writing to a man. 敬启者 (常用于正式函件或商务函件)
Dear Sir, Enclosed is a copy of my résumé for your consideration.
敬启者，兹附上我的简历一份，请予以考虑。
term of address for a man
a title used before the name of knight or baronet
先生
信号干扰比
选择资讯检索 (selective information retrieval)
语意资讯检索器 (semantic information retriever)
串联红外线
串列输入暂存器 (serial input register)
西格玛资讯检索系统
航天飞机成像雷达 (shuttle imaging radar)
欧洲最成功的风险资本公司之一Apax Partners的创始人罗纳德·科恩爵士(Sir Ronald Cohen)指出：一些最成功的创业者是专注于制作方法流程而不是产品。
sir 2． 先生（Sir）和 太太 （ Madam ）,是对地位较高、年龄较父老的一处尊称。使用时，也可以不带姓名。
离子色谱（IC）和表面绝缘电阻（SIR）是最先问世的高级测试方法，它们至今仍然在使用。离子色谱是用来精确测试和标定工艺基准值最常用的工具。
... skill技能;技巧 sir先生;阁下 madam女士;夫人 ...
Is everything in order, sir?
一切都正常吗，先生？
Are you ready to order, sir?
先生，可以点菜了吗？
Good morning, sir. Can I help you?
早上好，先生。您要点什么？
Last week,British billionaire Sir Richard Branson showed his new spaceship Enterprise at the Mojave Air and Space Port in California.
VOA : special.2009.12.18
Sir, we ought to teach the people that they are doing wrong in worshipping the images and pictures in the temple."
先生，我们应该告诫人们，他们不应该,崇敬寺庙里的肖像或照片“
1945年后的美国小说课程节选 : 耶鲁公开课
That's right. Louisiana Slim he's sometimes called. Yes, Sir. I sure have met Big Slim. And he used to work in the east Texas oil fields?"
对，人们有时叫他路易斯安那的细杆，是的先生我肯定,遇见过，他过去是不是经常在得克萨斯州东部的油田工作？“
1945年后的美国小说课程节选 : 耶鲁公开课
And when this happens,sir, the U.S.will be importing food, only there won't be any place from where to import it."
VOA : special.2009.11.10
A waiter in the play tells a customer, "If you need any Scotch or gin,Sir My number is Eighty-Six."
VOA : special.2010.01.08
"This double accolade is uniquely deserved, " said Sir Peter Stothard, chairman of the judges.
BBC: Man Booker Prize won by Hilary Mantel's Bring up the Bodies
The Conservatives said Sir Michael had echoed their view that UK troops had long been over-stretched.
"There would be no question of selling a Turner to buy a Hirst, " Sir Nicholas added.