This is the 2629th most frequent Dutch word.
jochem
"Jochem" is a Dutch male given name, equivalent to "Joachim" in English, and does not have a standalone meaning.
Jochem is used here as a proper noun, referring to a person's name.
Jochem speelt elke zondag voetbal met zijn vrienden.
Jochem plays soccer with his friends every Sunday.
Jochem is used here in a possessive form, indicating ownership of 'zijn boek' (his book).
Ik vroeg of dat Jochem zijn boek was.
I asked if that was Jochem's book.
Jochem is used here as a proper noun in dialogue, identifying the speaker in this context.