It is a character from the popular imagery that appears in expressions and various sayings and literature in the 19th century as in the zarzuela La rosa's saffron ( Jacinto Guerrero ) adaptation of the dog in the Manger by Lope de Vega y Carpio. Probably comes from carraco: old, achacoso, disabled and in popular language is a wildcard character burlesque, picturesque and generally negative as in these expressions: it is uglier than carracuca, is more dead than carracuca, is more just than carracuca, it is older than carracuca, more hungry than carracuca, is more lost than carracuca, is worse than carracuca...
