This is the 6496th most frequent Dutch word.
unnerstall
"Unnerstall" is not a standard Dutch word. It may be a surname or dialect term.
In this sentence, 'Unnerstall' is used as a proper noun, referring to the name of a specific person.
Unnerstall is de doelman van het team.
Unnerstall is the goalkeeper of the team.
Here, 'Unnerstall' is again a proper noun, further contextualized by possessing an action.
De actie van Unnerstall was reden tot discussie.
The action of Unnerstall was a reason for discussion.
In this instance, 'Unnerstall' shows possessive usage by referring to the accomplishments of an individual.