This is the 10432nd most frequent Russian word.
велосипедов
"Bicycles" (genitive plural form).
In this sentence, 'велосипедов' is the genitive plural form, used to indicate possession or quantity.
На парковке стояло много велосипедов.
There were many bicycles in the parking lot.
Here, 'велосипедов' is again the genitive plural form, used to express quantity.
Я видел несколько новых велосипедов в магазине.
I saw several new bicycles in the store.
In this case, 'велосипедов' is employed in the genitive plural form, for denoting a large, unspecified number.