English Reference
verb · adjective

detected

v. · adj.
US /dɪˈtɛktəd/ UK /dɪtˈɛktɪd/ de·tect·ed

  1. 01 B2 Upper Intermediate

    v.to have found or noticed something that was hard to see or hidden.

    v.to have discovered or identified the presence of something, especially something subtle, hidden, or faint.

    Simple

    The security system detected a small movement in the hallway late at night.

    In context

    The laboratory equipment detected trace amounts of the chemical in the water supply, prompting an immediate investigation by the local authorities.

    Usage

    Often used in the passive voice when describing scientific or criminal findings.

  2. 02 B2 Upper Intermediate

    adj.describing something that has been seen or found by a person or a machine.

    adj.referring to an object, signal, or quality that has been successfully identified or perceived.

    Simple

    The error remained detected but uncorrected for several weeks.

    In context

    Once the signal was detected, the researchers began the process of triangulating its point of origin across the desert.

    Usage

    Usually functions as a predicative adjective or within a passive construction.

    Teacher's tip

    Learners should be aware that 'undetected' is actually more common as a standalone adjective than 'detected'.

The UN's International Maritime Organization reported that an oil slick was detected after that incident.

BBC News· 14 Aug 2026

The first exoplanet was detected in 1992, the second in 1995.

The Guardian· 11 Aug 2026
This entry
Level B2 · Upper Intermediate
Frequency Common
Updated