Modern invented name, likely combining Kash and the suffix -don.
Kashdon is a contemporary American coinage. It likely blends the name Kash (a variant of Cash, referring to money or a hollow place) with the popular masculine suffix -don, found in names like Brandon or Landon.
Less common today
Kashdon isn't in the latest US Top 1000. It last peaked at #3,677 in 2017.
US births per 5-year period, 1990βpresent (SSA data).