Casyn(pr. like Jason but with a K) A woman in our playgroup named her daughter this after seeing it on the "board" at the hospital where she works (as an OB nurse). I think it is actually a form of "Jason."
Casyn is a modern creation, a blend of Casey + the popular -n ending. In 2010, Kaysen (the most popular spelling) was #1318 in the US top 7000 for girls and #142 for boys (Cason was the most popular spelling for boys).
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