This is the 11802nd most frequent Polish word.
kosiarkę
The Polish word "kosiarkę" means "lawnmower" (accusative case).
In this sentence, 'kosiarkę' is the accusative singular form of the noun 'kosiarka', used here as the direct object of the verb 'widzę' (I see).
Widzę kosiarkę w ogrodzie.
I see a lawnmower in the garden.
The word 'kosiarkę' appears as the direct object in the accusative singular, referring to the item purchased.
Kupiliśmy nową kosiarkę w sklepie.
We bought a new lawnmower at the store.
Here, 'kosiarkę' is used in the accusative singular form related to the verb 'potrzebuję' (I need), indicating the need for this specific object.