O.E. heorte, from P.Gmc. *khertan- (cf. O.S. herta, O.N. hjarta, Du. hart, O.H.G. herza, Ger. Herz, Goth. hairto), from PIE *kerd- "heart" (cf. Gk. kardia, L. cor, O.Ir. cride, Welsh craidd, Hittite kir, Lith. širdis, Rus. serdce "heart," Breton kreiz "middle," O.C.S. sreda "middle"). Spelling with -ea- is c.1500, by analogy of pronunciation with stream, heat, etc., but remained when pronunciation shifted. Most of the figurative senses were present in O.E., including "intellect, memory," now only in by heart. Hearty is late 14c.; heart-rending is from 1680s. Heartburn is mid-13c. Heart-strings (late 15c.) was originally literal, in old anatomy theory "the tendons and nerves that brace the heart." Heartland first recorded 1904 in geo-political writings of H.J. MacKinder.