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REFERENCE

grandfather

n. · v.
US //ˈɡɹænˌfɑðɝ// UK //ɡɹˈændfɑːðɐ// grand·fa·ther
  1. 1 parent's father (n.)
    A1 Beginner

    the father of your mother or your father.

    the male parent of one's father or mother.

    Example

    My grandfather tells us stories about what life was like when he was a boy.

    Example

    After retiring from the civil service, her grandfather spent most of his afternoons tending to the community garden.
  2. 2 male ancestor (n.)
    B2 Upper Intermediate Literary

    a male relative from a long time ago in your family history.

    a male ancestor or forefather.

    Example

    The traditions of our grandfathers are still important to our village today.

    Example

    The historian traced the family lineage back to their grandfathers who first settled in the valley during the eighteenth century.
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  1. 3 legacy data backup (n.)
    C2 Proficiency Technical Computing

    an older version of a computer file used for safety.

    the oldest generation of a three-generation backup rotation scheme, preceding the 'father' and 'son' files.

    Example

    The IT department keeps the grandfather tapes in a separate building for safety.

    Example

    In a standard rotation, the grandfather file is updated monthly and stored off-site to ensure data recovery in the event of a total system failure.
    • legacy backup
  2. 4 to exempt from new rules (v.)
    C1 Advanced American English Formal Law

    to allow someone to follow an old rule even after a new rule starts.

    to exempt a person or entity from a new regulation based on their previous status. Often used as 'grandfather in'.

    Example

    The city changed the building laws, but they grandfathered in the old houses.

    Example

    Existing homeowners were grandfathered into the previous tax bracket, sparing them from the sudden increase mandated by the new legislation.

    Usage

    Often appears in the phrasal form 'grandfather in' or as the passive 'be grandfathered'.
Etymology 1

The noun is derived from Middle English grandfadre, graundfadir, graunfadir, grauntfader, and other forms, from graunt (“big, large; great, important”) + fā̆der (“male parent, father; remoter male ancestor”), probably modelled after Middle French grandpere, grant pere (“male parent; remoter male ancestor”) (whence French grand-père); the English word is analysable as grand- + father. Superseded earlier eldfather, elderfather. The verb is derived from the noun.

Etymology 2

From grandfather clause: see grandfather (etymology 1) and clause.

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