1. The action, fact, or instance of occurring: The occurrence of snow is rare in these parts.
2. Something that takes place; an event or incident: worrisome occurrences.
Synonyms: occurrence, happening, event, incident, episode
These nouns refer to something that takes place or comes to pass. Occurrence and happening are the most general: an everyday occurrence; a happening of no great importance. Event usually signifies a notable occurrence: world events reported on the evening news. "Great events make me quiet and calm; it is only trifles that irritate my nerves" (Victoria).
Incident may apply to a minor occurrence: an incident that was blown out of proportion in the press. The term may also refer to a distinct event of sharp identity and significance: an incident that changed scientists' understanding of the phenomenon. An episode is an incident in the course of a progression or within a larger sequence: "Happiness was but the occasional episode in a general drama of pain" (Thomas Hardy).
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.