English Reference
verb · adjective

observed

v. · adj.
US /əbˈzɝvd/ UK /ɒbzˈɜːvd/ ob·served

  1. 01 B2 Upper Intermediate Science

    v.watched someone or something closely to learn about them.

    v.monitored or watched a subject with attention to detail, often for scientific or investigative purposes.

    Simple

    The scientists observed the birds for several weeks to see how they built their nests.

    In context

    The researchers observed the chemical reaction under a microscope, noting the precise moment the solution changed from clear to opaque.

    Usage

    Often used in the passive voice in scientific reporting.

  2. 02 B2 Upper Intermediate Formal

    v.obeyed a law, a rule, or a religious custom.

    v.complied with or adhered to a law, regulation, or religious tradition.

    Simple

    The silence was strictly observed during the ceremony to show respect.

    In context

    The local community has observed these traditional fasting laws for centuries, passing the customs down through generations.

    Usage

    Commonly used with abstract nouns like 'silence', 'tradition', or 'protocol'.

  3. 03 C1 Advanced Formal

    v.said something you noticed about a situation.

    v.made a remark or comment based on an observation.

    Simple

    He observed that the room was much colder than it had been yesterday.

    In context

    The chairman observed that the company's growth had slowed significantly in the final quarter of the fiscal year.

    Usage

    Typically followed by a 'that' clause.

  4. 04 C1 Advanced TechnicalFormal

    adj.describes a public holiday that is celebrated on a different day than usual.

    adj.pertaining to a public holiday celebrated on a date other than its traditional calendar date, usually to create a long weekend.

    Simple

    Since Christmas fell on a Sunday, the holiday was observed on Monday instead.

    In context

    The government announced that the national day would be an observed holiday on the following Friday to encourage domestic tourism.

Usage observed an increase · observed similar

This should reveal whether the patterns observed are unique to butterflies or also apply to other insects.

Phys.org· 17 Aug 2026

The energy output is far closer to that observed from black holes than stars.

The Guardian· 12 Aug 2026
This entry
Level B2 · Upper Intermediate
Frequency Common
Updated