ENGLISH
REFERENCE

sir

n. countable
A2 Elementary Oxford US //ˈsɝ// UK //sˈɜː// sir General-service Informal

n. a polite way to talk to a man you do not know, or a title for a teacher at school. You use it to show respect.

n. a formal or polite term of address for a man, especially one in a position of authority or a stranger. When used as a title for a knight or baronet, it is always capitalised and followed by a first name.


SIMPLE

Excuse me, sir, you dropped your wallet.

CONTEXTUAL

The students stood up and said 'Good morning, sir' when the history teacher entered the classroom.

Usage

Often used as a standalone address without a name; as a title, it must be followed by a first name (e.g., Sir Elton), never just a surname.

Pitfall

Hello Sir SmithHello Sir John / Hello Mr. SmithWhen used as a title of honour, 'Sir' must be followed by a first name, not a surname alone.

Idioms2 entries

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