English Reference
noun

occurrence

n.
US /əˈkɝəns/ UK /əkˈɜːɹəns/ oc·cur·rence UK spelling occurrence's, occurrence's

  1. 01 B2 Upper Intermediate

    something that happens, especially an event that is not planned.

    an instance of something happening; a specific event or incident.

    Simple

    Power cuts are a common occurrence during the stormy winter months.

    In context

    The sudden appearance of the rare bird in a suburban garden was such an unusual occurrence that it drew birdwatchers from across the country.

    Usage

    Often used with adjectives like 'common', 'rare', or 'everyday'.

    Pitfall
    It was a strange occurance. It was a strange occurrence.

    The word is frequently misspelled; remember it has a double 'c' and a double 'r'.

  2. 02 C1 Advanced AcademicTechnical Science

    the fact of something existing or being found in a place.

    the fact or frequency of something appearing or existing within a particular place or dataset.

    Simple

    Scientists are studying the occurrence of microplastics in the local river.

    In context

    The researchers noted a high occurrence of specific mineral deposits along the fault line, suggesting a complex geological history.

    Usage

    Often followed by the preposition 'of'.

    Teacher's tip

    In academic writing, this sense is used to discuss how often a specific feature or substance appears in a sample.

  3. 03 C2 Proficiency TechnicalFormal Science

    the way a verb describes an action happening over time.

    the lexical aspect or 'aktionsart' of a verb or predicate, specifically regarding how it unfolds in time.

    Simple

    The professor explained how the occurrence of the verb changed its meaning.

    In context

    In formal semantics, the occurrence of a predicate is analyzed based on whether the action has a natural endpoint or continues indefinitely.

    Usage

    Used as a technical term in linguistics and grammar.

    Teacher's tip

    This is a highly specialized term; most learners will only encounter it in advanced linguistics textbooks.

    aspectaktionsart

Usage explain occurrence · occurrence of · predict occurrence

From 2001 to 2003, my laboratory studied the occurrence of those protozoa at six sewage treatment plants – one each in Arizona and California and four in Florida.

The Conversation· 10 Aug 2026

Machine learning requires ample training data in order to make future predictions, but extreme events are by nature rare occurrences.

Ars Technica· 8 Aug 2026

From Middle French occurrence, from Medieval Latin occurrentia. Morphologically occur + -ence.

Etymology adapted from Wiktionary, available under CC BY-SA 4.0.

This entry
Origin la-med occurrentia
Level C1 · Advanced
Frequency Frequent
Updated