This is the 501st most frequent Polish word.
poznaniu
"Poznaniu" is the locative case of "Poznań," meaning "in Poznań" (a city in Poland).
In this sentence, 'poznaniu' is used as a noun derived from the verb 'poznać', referring to the action of getting to know someone.
Po poznaniu nowych kolegów, trudno było się rozstać.
After getting to know new friends, it was hard to leave.
In this example, 'poznaniu' refers to the initial meeting or introduction between two people.
Miałem okazję porozmawiać z nią po naszym pierwszym poznaniu.
I had the opportunity to talk to her after our first meeting.
Here, 'poznaniu' is used to indicate the process of becoming familiar with something, referring to understanding or learning.