This word is from the Spanish becerro, meaning a calf under three years of age.
bi·sí·ro
young cow or bull
young cow or bull
munting bisiro
small calf
bisirong toro
young bull
wangis ng mata ng bisirong-toro ni Lupeyo
like the eyes of Lupeyo’s bull-calf
Filipinos also sometimes use the word bisiro to refer to a young horse like a pony.
MGA KAHULUGAN SA TAGALOG
bisíro: batàng kabayo
bisírong toro: batàng laláking báka