Son of Maud or son of Matthew
Madasyn is a modern creative spelling of Madison. It originated as an English surname meaning 'son of Maud' (a form of Matilda) or 'son of Matthew', but it has evolved into a popular feminine given name in the United States.
Less common today
Madasyn isn't in the latest US Top 1000. It last peaked at #4,886 in 2011.
US births per 5-year period, 1990βpresent (SSA data).