This is the 15387th most frequent Polish word.
spacerujące
"Spacerujące" means "walking" or "strolling" (present participle, plural form).
Here, 'spacerujące' is used as a present participle adjective describing the noun 'osoby' (people), indicating that the people are engaged in walking.
Spacerujące osoby podziwiały piękno parku.
The walking people admired the beauty of the park.
In this sentence, 'spacerujące' describes the noun 'koty' (cats), again serving as an adjective indicating the action the cats are performing.
Widzę spacerujące koty na ulicy.
I see walking cats on the street.
Here, 'spacerujące' functions similarly to the previous examples, modifying the noun 'dzieci' (children) to show that the children are in the act of walking.