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observe

v.
US //əbˈzɝv// UK //ɒbzˈɜːv// ob·serve
  1. 1 to watch carefully (v.)
    B2 Upper Intermediate Science

    to watch someone or something carefully, often to learn something new.

    to watch or monitor something with attention to detail, often for scientific or investigative purposes.

    Example

    The scientists stayed up all night to observe the behavior of the birds.

    Example

    Researchers spent several months in the field to observe how the local wolf population interacted with neighboring packs during the winter.

    Usage

    Often used with a direct object or a 'that' clause.
  2. 2 to follow a rule (v.)
    B2 Upper Intermediate Formal

    to obey a law, a rule, or a religious custom.

    to comply with or adhere to a law, regulation, or religious tradition.

    Example

    Drivers must observe the speed limit to keep the roads safe.

    Example

    The company failed to observe the safety regulations, resulting in a significant fine from the environmental protection agency.

    Usage

    Transitive; takes a direct object representing the rule or law.
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  1. 3 to celebrate a holiday (v.)
    B2 Upper Intermediate Formal

    to mark or celebrate a special day, like a holiday.

    to acknowledge or celebrate a holiday, anniversary, or significant event through traditional practices.

    Example

    Many people observe a moment of silence to remember the soldiers.

    Example

    The embassy will be closed on Monday as the staff observe the national holiday of their home country.
  2. 4 to make a comment (v.)
    C1 Advanced Formal

    to say or write a remark about something you have noticed.

    to make a verbal or written remark; to comment on a situation or fact.

    Example

    "It is getting quite late," she observed as she looked at the clock.

    Example

    The critic observed that the director's latest film lacked the emotional depth of his earlier masterpieces.

    Usage

    Often introduces a direct quote or a 'that' clause.
Origin

From Middle French observer, from Old French observer, from Latin observō (“to watch”), from ob- (“before”) + servō (“to keep”), from Proto-Indo-European *ser- (“to guard”). Cognate with Gothic 𐍃𐌰𐍂𐍅𐌰 (sarwa, “weapons, armour”), Old English searu (“device”).

Word family

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