This is the 4153rd most frequent German word.
aufgepasst
"Aufgepasst" means "paid attention" or "watched out."
The word 'aufgepasst' here refers to being attentive or careful about one's surroundings.
Beim Überqueren der Straße hat sie aufgepasst.
She paid attention while crossing the street.
In this sentence, 'aufgepasst' is used to indicate a lack of attention leading to a mistake.
Ihr hättet besser aufgepasst, dann wäre der Fehler nicht passiert.
You should have paid better attention; then the mistake wouldn't have happened.
Here, 'aufgepasst' is used as an imperative to demand attention or focus from others.