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ruler

n. · v.
US //ˈɹuɫɝ// UK //ɹˈuːlɐ// ruler
  1. 1 measuring tool (n.)
    A1 Beginner

    a flat, straight tool used for measuring length or drawing straight lines.

    a rigid, flat instrument with marked graduations used for measuring linear distance or as a straightedge.

    Example

    Use a ruler to make sure the line is exactly ten centimetres long.

    Example

    The student used a wooden ruler to measure the dimensions of the specimen before sketching it in her notebook.
  2. 2 leader (n.)
    A2 Elementary

    a person who has the power to control a country or group, like a king or queen.

    a person who exercises supreme authority or dominion over a territory or people.

    Example

    The ancient ruler built many beautiful temples during his long reign.

    Example

    Historians often debate whether the ruler was a benevolent visionary or a tyrant who prioritised expansion over the welfare of his subjects.
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  1. 3 to hit with a ruler (v.)
    C2 Proficiency Archaic

    to hit someone with a ruler as a punishment.

    to strike a person, typically a student, with a ruler as a form of corporal punishment.

    Example

    In the old days, teachers might ruler a student for being late.

    Example

    The memoir describes a harsh Victorian classroom where the master would ruler any child who failed to recite their verses perfectly.

    Usage

    This verb is transitive and takes a direct object, usually a person.

    Teacher's tip

    This sense is archaic and refers to historical school discipline; it is not used in modern educational contexts.
Origin

From Middle English reuler; equivalent to rule + -er.

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