coincidentally

IPA/kəʊˌɪnsɪˈdentəli/
KK[koˌɪnsɪdˈɛntəli]IPA/kəʊˌɪnsɪˈdentəli/

coincidentally — adverb

1. happening because of chance rather than through planning or expectation — especi

1.adverbB2
Definition

happening because of chance rather than through planning or expectation — especially when two things unexpectedly connect, happen together, or turn out to be related without anyone intending that result.

Example

Coincidentally, Mateo and Devika discovered that they had both grown up on the same street.

sentence-initial position for whole-clause comment

Bao ran into his old neighbour, who coincidentally was on the same flight.

mid-clause modifier inside a relative clause

Common collocations
  • purely coincidentally
  • entirely coincidentally
  • quite coincidentally
  • perhaps coincidentally
  • not coincidentally
  • coincidentally enough
Synonyms
  • by chance

    less formal, neutral register; can be used in everyday conversation

  • fortuitously

    more formal, often implies a lucky or favourable outcome

  • accidentally

    focuses on the lack of intention; often used for mishaps rather than surprising alignments

Antonyms

Grammar Patterns

coincidentally, [clause]

[clause] ... coincidentally [verb] ...

[clause], coincidentally

Usage Note

Coincidentally can appear in three positions in a sentence: at the start as a sentence adverb (commenting on the whole clause), mid-clause right before the main verb, or at the end after an intensifier like 'purely' or 'entirely'. The sentence-initial position is the most common in writing.

Common Mistakes

Coincidentally I planned to meet my friend at 3 PM.
I planned to meet my friend at 3 PM
it was not coincidental at all.' — 'coincidentally' describes unplanned chance, not any event that simply happens.
Coincidentally, she broke her leg while skiing.
Coincidentally, she and her cousin both broke their legs in separate accidents on the same day.
A single negative event is usually described as an 'accident', not a 'coincidence'; the word works best when two things unexpectedly align.

Word family

Synonym discussion

Sense: adverb/1

Coincidentally, by chance, fortuitously, accidentally, and serendipitously all describe events that happen without being planned, but they differ in connotation and use. By chance is the most neutral and everyday option ('We met by chance at the library'). Fortuitously carries a positive meaning — it implies the unplanned event turned out well ('Fortuitously, the train was delayed, so I caught up on my reading'). Accidentally focuses on unintended results and often describes mistakes or mishaps ('I accidentally deleted the file'). Serendipitously adds a sense of happy discovery or good luck ('She serendipitously found the missing earring under the sofa'). Coincidentally, by contrast, is best used when two or more separate things unexpectedly align in an interesting way — not just a lucky find, but a surprising connection between events or people.

by chancefortuitouslyaccidentally ↗serendipitously

Common collocations

Adverbs

Phrases

  • coincidentally enough
  • completely coincidentally

Etymology

LatinFrenchEnglish

Coincidentally comes from the Latin prefix 'co-' meaning 'together' and 'incidere' meaning 'to fall upon or happen'. It entered English through French in the 17th century, first appearing as 'coincide' (to occupy the same space or time), followed by 'coincident' (the adjective) and later 'coincidentally' (the adverb). The original sense of 'falling together' in time or space gradually expanded to cover any surprising alignment of events.

First known use

1837

1837, in the meaning defined at sense 1