From The Collaborative International Dictionary of English v.0.48 [gcide]:
Casa \Ca"sa\, n. [Sp. or It., fr. L. casa cabin.]
A house or mansion. [Sp. Amer. & Phil. Islands]
I saw that Enriquez had made no attempt to modernize
the old casa, and that even the garden was left in its
lawless native luxuriance. --Bret Harte.
[Webster 1913 Suppl.]