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cacho (2) m. (Noun) "surmullet"
From Vulgar Latin *cattulus "puppy," from Latin catulus "animal young." From Proto-Italic *kat-elo- 'id.' Of uncertain origin, unlikely to be from Proto-Indo-European.
Indo-European
Romance
Portuguese cátulo
Italic
Umbrian katel "sacrificial animal"
Germanic
Old Icelandic haðna "kid," Middle High German hatele "goat"
Balto-Slavic
Czech kót "breeding period," Polish kot (defined by Derkson (2015) as "place where forest animals young"), BCS kȏt "breeding period," Slovene kòt "brood"
de Vaan, M. Etymological Dictionary of Latin and Other Italic Languages. BRILL. 2014.
Dictionnaire Étymologique Roman. Online. Ed. by É. Buchi & W. Schweickard. 2018. http://www.atilf.fr/DERom.
Real Academia Española. Diccionario de la lengua española. Online. 23rd ed. Madrid: Espasa Calpa. 2014. http://www.rae.es/.
Roberts, E. A. A Comprehensive Etymological Dictionary of the Spanish Language with Families of Words based on Indo-European Roots. 2 vols. Xlibris Corporation. 2014.