偶然(ぐうぜん)に

ぐうぜんに
adverb
by chance; accidentally; coincidentally
abstract
1. by chance; accidentally; coincidentally
in an unplanned or unexpected manner, without intention or design
偶然(ぐうぜん)に旧友(きゅうゆう)に会(あ)った。
I ran into an old friend by chance.
偶然(ぐうぜん)にその店(みせ)を見(み)つけて入(はい)ってみた。
I happened to find the shop and decided to go in.
偶然(ぐうぜん)に同(おな)じ電車(でんしゃ)に乗(の)り合(あ)わせたのがきっかけで親(した)しくなった。
We became close after coincidentally being on the same train.

The adverbial form of 偶然(ぐうぜん) (coincidence). Can also be used without に as an adverb (偶然(ぐうぜん)会(あ)った is equally common). The に form emphasizes the manner in which something happened.

Common collocations

Similar words

  • たまたま: by chance, happen to — more casual and spoken; often implies a lucky or unlucky coincidence
  • 思(おも)いがけず: unexpectedly — emphasizes the surprise element
  • 図(はか)らずも: unexpectedly, by a twist of fate — literary, often for fortunate or ironic coincidences

Common patterns

Both 偶然(ぐうぜん) and 偶然(ぐうぜん)に function as adverbs. The form without に is slightly more common in casual speech.