This is the 110th most frequent Finnish word.
jolloin
"Jolloin" means "when" (in the sense of at which time).
In this sentence, 'jolloin' refers to 'during which', specifying a particular moment or circumstance associated with another event.
Kävin kaupassa, jolloin tapasin vanhan ystäväni.
I went to the store, during which I met an old friend.
In this example, 'jolloin' conveys the meaning of 'when', indicating the time or event during which an action occurred.
Se oli hetki, jolloin tajusin totuuden.
It was the moment when I understood the truth.
Here, 'jolloin' connects a specific circumstance (a rainy day) to a resulting action (deciding to stay home), emphasizing the condition's influence on the decision.