This is the 5981st most frequent Swedish word.
janken
"Janken" is not a standard Swedish word; it may refer to "rock-paper-scissors" in Japanese (jan-ken) but is not used in Swedish.
In this sentence, 'Janken' is used as a proper noun, likely someone's name.
Janken såg väldigt glad ut efter att ha vunnit tävlingen.
Janken looked very happy after winning the competition.
Here, 'janken' is used as a common noun, possibly referring to an object or something peculiar not immediately clear in meaning.
Jag undrade vad janken gjorde på bordet, det var inte där förut.
I wondered what the janken was doing on the table, it wasn't there before.
In this usage, 'janken' refers to the game of rock-paper-scissors, which is a borrowed term from Japanese (じゃんけん).