Princess
Sady is a diminutive of Sarah, which is a Hebrew name meaning princess. While traditionally a nickname, it has occasionally been used as a standalone name, though it is much rarer than the 'Sadie' spelling.
Less common today
Sady isn't in the latest US Top 1000. It last peaked at #7,777 in 2008.
Paraguayan professional footballer
US births per 5-year period, 1990βpresent (SSA data).