This is the 11643rd most frequent Polish word.
klubowi
"Klubowi" means "to the club" or "club's" (dative form in Polish).
In this sentence, 'klubowi' is the dative case of the noun 'klub' (club), indicating the indirect object receiving the gratitude.
Jestem bardzo wdzięczny klubowi za wsparcie.
I am very grateful to the club for the support.
Here, 'klubowi' is again in the dative case, showing the recipient of the action of dedication.
Pisarz dedykował swoją książkę lokalnemu klubowi.
The writer dedicated his book to the local club.
'Klubowi' is used in the dative case to indicate the entity receiving help.