This is the 13822nd most frequent Polish word.
pokoleniom
"Generations" (dative plural form).
Here, 'pokoleniom' is used in the dative case to indicate 'to generations', showing the target of the action of passing knowledge.
Przekazuję wiedzę pokoleniom, aby zachować tradycje.
I pass knowledge to generations to preserve traditions.
'Pokoleniom' is implied in this sentence as it represents a group affected by certain actions, even though it's expressed in a different grammatical case here.
Nasze działania mają znaczenie dla przyszłych pokoleń.
Our actions have significance for future generations.
'Pokoleniom' is again in the dative case, indicating the recipient of the transferred history.