Sir

Sir is an honorary title.

Military use

The common use of Sir in stead of the rank specific address for a military, police or other officer is rather specific to English, in most languages no such general address is considered respectful, or the two are combined, as in German Herr followed by the rank.

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Possibly the shortness of the word helps explain another, in a sense compensating, idiomatic practice in English: putting Sir both in front and behind an obedient response given in clear voice to the senior, especially during drill, e.g. 'Sir, yes, sir!'

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