Princess
Saidey is a modern phonetic spelling variant of the Hebrew name Sadie, which originated as a diminutive of Sarah. It carries the traditional meaning of princess or noblewoman, though this specific spelling is quite rare.
Less common today
Saidey isn't in the latest US Top 1000. It last peaked at #13,367 in 2010.
US births per 5-year period, 1990βpresent (SSA data).