This is the 3870th most frequent Swedish word.
kriminellt
"Kriminellt" means "criminal" in English.
Here, 'kriminellt' is used as an adjective describing an action that is against the law or morally wrong.
Det är kriminellt att stjäla saker.
It is criminal to steal things.
In this sentence, 'kriminellt' describes the way someone acted, attributing the nature of the action as illegal.
Han agerade kriminellt när han bröt sig in i huset.
He acted criminally when he broke into the house.
Here, 'kriminellt' modifies 'gäng', describing the group as engaging in law-breaking activities.