Modern invented name, possibly a combination of De- and Asia
Deaysia is a contemporary American coinage. It likely follows the late 20th-century trend of adding the prefix 'De-' to established names or place names like Asia, which refers to the continent and carries connotations of sunrise or the east.
Less common today
Deaysia isn't in the latest US Top 1000. It last peaked at #9,397 in 2007.
US births per 5-year period, 1990βpresent (SSA data).