Meaning

noun a painful burning sensation in the chest caused by gastroesophageal reflux (backflow from the stomach irritating the esophagus); symptomatic of an ulcer or a diaphragmatic hernia or other disorder

originFrom Middle English hertbryne, herte-bren (“lust", also "heartburn”, literally “heart burn”), equivalent to heart + burn. Compare also Middle English herte-brennyng (“anger, bitterness, heartburn”, literally “burning of/in the heart, heart-burning”). Compare also Ancient Greek καρδιαλγία (kardialgía), from καρδία (kardía, “heart”) + ἄλγος (álgos, “pain”). From being a burning sensation near the…

Etymology from Wiktionary, CC BY-SA 3.0