English Reference
noun · verb

sir

n. · v.
US /ˈsɝ/ UK /sˈɜː/ sir

  1. 01 A2 Elementary Formal

    n.a polite way to address a man, especially if you do not know his name.

    n.a respectful term of address used for a male person, typically when his name is unknown or to show deference.

    Simple

    Excuse me, sir, I think you dropped your wallet on the sidewalk.

    In context

    The waiter approached the table and asked, 'Are you ready to order now, sir?'

    Usage

    Usually used as a standalone vocative without a following name.

    Pitfall
    Excuse me, Sir John, can you help me? Excuse me, sir, can you help me?

    Use 'sir' alone when you don't know the name. Only use 'Sir' with a name if the person has a formal title like a knighthood.

    madamma'am
  2. 02 B1 Intermediate British EnglishFormal

    n.a title used before the first name of a knight or baronet.

    n.the titular prefix used before the forename of a knight or baronet.

    Simple

    Sir Isaac Newton was a famous scientist who studied gravity.

    In context

    The Queen granted him a knighthood, and he is now formally addressed as Sir Anthony.

    Usage

    Always capitalized and followed by a given name.

    Pitfall
    I met Sir Smith yesterday. I met Sir Elton yesterday.

    The title 'Sir' must be followed by a first name (Sir Elton) or a full name (Sir Elton John), never just a surname.

  3. 03 B1 Intermediate British English

    n.a way for students to address a male teacher in some countries.

    n.a conventional term of address used by students for a male school teacher.

    Simple

    Please, sir, can I go to the bathroom?

    In context

    In many British secondary schools, it remains standard practice for pupils to address male staff members simply as 'sir'.

    Usage

    Commonly used as a vocative in educational settings.

  4. 04 C1 Advanced Informal

    v.to call someone 'sir' when you speak to them.

    v.to address a person using the honorific 'sir', often to show extreme respect or military discipline.

    Simple

    Don't sir me—we've been friends for years.

    In context

    The recruit was instructed to sir every officer he encountered on the base.

    Usage

    Used transitively; the object is the person being addressed.

This entry
Level A2 · Elementary
Frequency Very common
Updated