# coincidence

Pronunciation: say "koh-IN-si-duhns" US /koʊˈɪnsɪdəns/, UK /kəʊˈɪnsɪdəns/, AUS /kəʉˈɪnsɪdəns/

## Noun

1. The appearance of a meaningful connection between events that are in fact unrelated.
   - Simple: When two events seem connected on purpose but really happen by chance.
   - _The detective argued that the matching timestamps were no coincidence._
   - _By sheer coincidence, both novelists set their stories in the same tiny village._
2. The state of two or more things occupying the same position or happening at the same moment.
   - Simple: When two things are in the same spot or happen at the same time.
   - _The coincidence of the planets along a single line is a rare event._
   - _Surveyors confirmed the coincidence of the new marker with the old boundary wall._
3. A point at which two functions or mappings take the same value.
   - Simple: A point where two math functions give exactly the same value.
   - _Fixed-point theorems guarantee that certain pairs of maps possess at least one coincidence._
   - _The proof reduces the problem to locating a coincidence of the two continuous functions._
4. A fixed point of a correspondence: a point of a variety that maps to itself under the correspondence.
   - Simple: In geometry, a point that matches itself when a rule pairs points together.
   - _Each coincidence corresponds to a point left fixed by the algebraic correspondence._
   - _The number of coincidences of a correspondence on a curve follows a classical formula._

## Origin

From French coïncidence; by surface analysis, coincide plus the suffix -ence.

Source: DictionaryAI, https://dictionaryai.com/define/coincidence (written from Wiktionary data, CC BY-SA 4.0: https://creativecommons.org/licenses/by-sa/4.0/).