A more thorough explanation:

gisetaker

An old-fashioned word that means the same thing as AGISTER.

• The gisetaker was responsible for taking care of the animals on the land.
• The gisetaker collected fees from people who wanted to graze their animals on the land.

These examples show that a gisetaker is someone who takes care of animals on a piece of land and collects fees from people who want to use that land for grazing. This word is not commonly used anymore, but it was once a common term for this type of job.