This is the 7052nd most frequent Polish word.
heleny
"Heleny" is the plural form of "Helena," a proper noun referring to the name Helen.
In this sentence, "heleny" is used genitively to refer to Helen from mythology.
Heleny to królowa w mitologii greckiej.
Helen is a queen in Greek mythology.
Here, "Heleny" indicates plural accusative form of the name Helen.
Spotkałem dwie Heleny na przyjęciu.
I met two Helens at the party.
Though "Helennę" is used, "Heleny" would indicate genitive or plural forms such as "of Helen" or several Helens.