This is the 6016th most frequent Swedish word.
jonson
"Jonson" is not a Swedish word; it is typically a surname.
Here, "Jonson" is used as a proper noun, referencing a person's name.
Jonsons bok var en bästsäljare i år.
Jonson's book was a bestseller this year.
In this sentence, "Jonson" is again a proper noun, referring to a professional builder or creator of the house.
Huset som Jonson byggde är verkligen imponerande.
The house that Jonson built is truly impressive.
Here, "Jonson" is used to describe a specific strategy named after a person, presumably Jonson, implying that the word is part of a branded or well-known concept.