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birthday

US //ˈbɝθˌdeɪ// UK //bˈɜːθdeɪ// birth·day
  1. 1 anniversary of birth (n.)
    A1 Beginner

    the day each year that is the same date as the day you were born.

    the annual anniversary of the day on which a person was born.

    Example

    She received many cards and presents for her tenth birthday.

    Example

    Although he usually dislikes being the centre of attention, he agreed to a small family dinner to mark his fiftieth birthday.

    Usage

    often used with the verbs 'be', 'have', or 'celebrate'
    Pitfall
    I have birthday today.
    It is my birthday today.

    In English, we usually say 'It is my birthday' or 'Today is my birthday' rather than 'I have birthday'.

  2. 2 a party (n.)
    A2 Elementary Informal

    a party or celebration for someone's birthday.

    a social gathering or celebratory event held to commemorate a birth anniversary.

    Example

    Are you coming to my birthday next Saturday night?

    Example

    The entire office was invited to the surprise birthday held in the staff lounge during the lunch hour.
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  1. 3 founding anniversary (n.)
    B2 Upper Intermediate

    the anniversary of the day something like a company or country started.

    the anniversary of the day on which an institution, organization, or nation was established.

    Example

    The city is planning a huge parade for its 200th birthday.

    Example

    The university celebrated its centenary birthday with a series of lectures and a formal gala for alumni.
  2. 4 to celebrate (v.)
    C2 Proficiency Informal Slang

    to celebrate your birthday.

    to engage in festivities or activities associated with one's birth anniversary. Intransitive use.

    Example

    We are going to birthday in the city this weekend.

    Example

    The group decided to birthday in style by booking a private suite at the most expensive hotel in the district.

    Usage

    the verb is intransitive and does not take a direct object
Origin

From Middle English birthdai, birtheday, from Old English ġebyrddæġ (“birthday”), influenced by Old Norse burðr, equivalent to birth + day. Compare Saterland Frisian Gebuursdai (“birthday”), Dutch geboortedag (“birthday”), Low German Geboortsdag (“birthday”), German Geburtstag (“birthday”), Norwegian bursdag, gebursdag (“birthday”). Eclipsed non-native Middle English nativitee (“birth, nativity, birthday”), from Old French nativité, nativited, from Latin nātīvitas.

Idioms1 entry

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