gabachos is incorrectly written and it should be written as "Gavachos" being its meaning:
The term should really be written as Gavachos. It is a way to refer in derogatory manner the French ( that also tells them Gauls, frenchies, francornos, francinerosos, etc. ). The origin of the term refers to be coming from the banks of the river Gave ( Whether River Gave of Oloron; 39 or ) River Gave de Pau, in France.