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diary

n. · v.
US //ˈdaɪɝi// UK //dˈaɪəɹi// di·ary
  1. 1 personal record (n.)
    A2 Elementary

    a book where you write down your private thoughts and what happens to you each day.

    a daily record of personal experiences, observations, and reflections, typically intended for private use.

    Example

    She wrote in her diary every night before going to sleep.

    Example

    The historian discovered a hidden diary that provided a vivid, first-hand account of life during the occupation.

    Pitfall
    I bought some fresh milk at the diary.
    I bought some fresh milk at the dairy.

    Do not confuse 'diary' (a book for writing) with 'dairy' (related to milk).

  2. 2 appointment book (n.)
    B1 Intermediate British English

    a book or app used to record future appointments and meetings.

    a calendar or personal organiser used to schedule future engagements and deadlines.

    Example

    Let me check my diary to see if I am free for lunch next Tuesday.

    Example

    The executive's diary was so tightly packed with back-to-back meetings that she barely had time for a coffee break.

    Usage

    Commonly used in British English where American English speakers would prefer 'calendar' or 'planner'.

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  1. 3 to record an event (v.)
    C1 Advanced Formal

    to write something down in a diary or to schedule a meeting.

    to enter an appointment or event into a diary; to maintain a regular journal of activities.

    Example

    We need to diary a follow-up meeting for next month.

    Example

    The legal team was instructed to diary every interaction with the client to ensure a complete paper trail for the audit.

    Usage

    Often used as a transitive verb in professional or legal contexts.

Etymology 1

From Latin diārium (“a daily allowance for soldiers, in Late Latin also ‘diary’”), neuter of *diārius, from diēs (“a day”) (whence also journal). Cognate with Spanish diario (“daily; diary”).

Etymology 2

From Latin diārius.

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