This is the 7429th most frequent Russian word.
григорьевича
"Григорьевича" is a patronymic form meaning "son of Grigory."
Here, 'Григорьевича' is a patronymic used in formal references or to show possession.
Это книга Александра Григорьевича.
This is Alexander Grigoryevich's book.
In this case, 'Григорьевича' acts as a respectful address using just the patronymic.
Я слышал рассказ от Григорьевича.
I heard a story from Grigoryevich.
Here, 'Григорьевич' is used colloquially to refer to a person respectfully yet casually.