1) A hollow muscular organ that pumps the blood through the circulatory
system by rhythmic contraction and dilation. In vertebrates there may
be up to four chambers (as in humans), with two atria and two
M.E. herte, from O.E. heorte "heart breast, soul, spirit, will, desire; courage; mind, intellect;" cf. O.Saxon herta, O.Frisian herte, O.Norse hjarta, Du. hart, O.H.G. herza, Ger. Herz; cognate with Pers. del, as below; PIE root *kerd- "heart."
Del "heart" (Pashtu z'rrah, zyah; Baluci zirde "heart, mind, soul;" Kurd. zar; Sogd. žyâwar); Mid.Pers. dil; Av. zərəd-; cf. Skt. hrd-; Gk. kardia; L. cor "heart" (Fr. cœur; Sp. corazon, It. cuore); Russ. serdtse; Arm. sirt; E. heart, as above.