coincidence

/koʊˈɪn·sɪ·dəns/, /-səˌdens/ n [C/U]

Definition

› an occasion when two or more things happen at the same time, esp. in a way that is unexpected or unlikely, or the unlikely fact of such things happening at the same time: [C] Was our meeting here a coincidence? [U] By coincidence, both teams happen to be coached by men.

(Definition of coincidence n from the Cambridge Academic Content Dictionary © Cambridge University Press)