This is the 3447th most frequent Polish word.
zaskoczeniem
"Zaskoczeniem" means "a surprise" in English.
The noun 'zaskoczeniem' is used to indicate a sense of unexpectedness, referring to the feeling or event of surprise experienced.
Jego decyzja była dla mnie dużym zaskoczeniem.
His decision was a big surprise to me.
Here, 'zaskoczeniem' is part of a descriptive structure to emphasize the unexpected nature of the quick arrival.
Zaskoczeniem dla nas było, że przyszła tak szybko.
The surprise for us was that she arrived so quickly.
In this sentence, 'zaskoczenia' is a singular noun in the genitive case, depicting a surprising event experienced during the party.