celos
/ˈθelos/ · B1 · noun · m
jealousy
celos = zeal: same Latin zelus that gave English zealous and jealous
Latin zelus (from Greek zēlos, fervour) became both zeal and jealousy. In the plural, celos means jealousy (tener celos). In the singular, celo means zeal or an animal's heat or rut (estar en celo).