The ark of the covenant was made from Acacia wood. Very important wood to Jews & Christians in the Bible. It is a lovely sounding name and cool meaning in my opinion. Casey could be a nice nickname, especially if it sounds too odd or exotic to you.
Acacia is a genus of shrubs and trees belonging to the subfamily Mimosoideae of the family Fabaceae, first described in Africa by the Swedish botanist Linnaeus in 1773.Acacias are also known as thorntrees or wattles, including the yellow-fever Acacia and umbrella acacias.