I’m pretty sure it’s is a shortened form of Horcasitas, from Juan Vicente de Güemes Padilla Horcasitas y Aguayo, 2nd Count of Revillagigedo, the Viceroy of New Spain who sent an exploration expedition under Francisco de Eliza to the Pacific Northwest in 1791.

https://en.wikipedia.org/wiki/Juan_Vicente_de_G%C3%BCemes,_2...