Wages, rewards, or mercies
A creative phonetic spelling of the Spanish name Mercedes. It ultimately derives from the Latin 'merces', referring to the Virgin Mary as 'Maria de las Mercedes' (Mary of Mercies).
Less common today
Mersadies isn't in the latest US Top 1000. It last peaked at #3,768 in 2001.
US births per 5-year period, 1990βpresent (SSA data).