What does coincidental mean?
Coincidental is an adjective describing events that occur together by chance, with no causal link or deliberate arrangement between them. When two unrelated things happen at the same time, in the same place, or in a strikingly similar way, we call the connection coincidental — remarkable-seeming, yet unplanned. The word carries an interesting double edge: it can simply acknowledge luck ('meeting you here was purely coincidental'), but it also often functions skeptically, hinting that a supposedly accidental alignment may in fact have hidden causes. This makes it a favorite of disclaimers, detectives, and doubters alike. Derived from Latin roots meaning 'to fall upon together,' it entered English alongside its noun cousin 'coincidence' during the early modern period. It is a useful word precisely because it names a gap between what looks designed and what merely happens — one of the most human distinctions there is.
adjectiveHappening by mere chance, without any causal connection or deliberate arrangement; occurring at the same time or place in a way that seems remarkable but is unplanned.
- Occurring by chance rather than by plan, design, or causal connection — especially when two things happen together in a way that seems meaningful but is not.
"Meeting my old college roommate in a Tokyo bookshop was entirely coincidental."
"The similarity between the two plotlines was purely coincidental; the authors had never met."
"It seemed too neat to be coincidental that the power failed just as she opened the safe."
The disclaimer 'any resemblance to actual persons is purely coincidental' appears in nearly every film and novel — making this one of the most quoted legal phrases in popular culture.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of coincidental
Coincidental derives from the Medieval Latin verb 'coincidere,' formed from 'co-' (together) and 'cidere' (to fall), literally 'to fall upon together.' English adopted 'coincide' in the early 18th century, with the adjective 'coincidental' following later from the noun 'coincidence.' It shares this root family with 'incident' and 'occasion,' all descendants of the Latin verb 'cadere' (to fall).
Related word forms
How coincidental is actually used
Neutral in register, though it often carries a faintly skeptical connotation: speakers frequently use it to suggest that a 'coincidental' event may actually be connected. The phrase 'purely coincidental' is a fixed legal-style disclaimer. More formal than 'by chance,' less loaded than 'ironic.'
Easily confused with coincidental
'Coincident' means occurring at the same time, while 'coincidental' emphasizes that the shared timing is a matter of chance rather than design.