noun, masculine/esˈtomaɡo/plural: estómagos
estómago is masculine in Spanish.
stomach (an organ in animals that stores food in the process of digestion)
“Me siento enferma del estómago ahora mismo.” — I feel sick to my stomach right now.
Related: tener mariposas en el estómago
Inherited from Old Spanish estomago (“maw”), from Latin stomachus, from Ancient Greek στόμαχος (stómakhos, “gullet; stomach”), from στόμα (stóma, “mouth”).