Why turkey has the same name as Turkey
"back of the foot," Old English hela, from Proto-Germanic *hanhilon (cf. Old Norse hæll, Old Frisian hel, Dutch hiel), from PIE *kenk- (3) "heel, bend of the knee" (cf. Old English hoh "hock").
Meaning "back of a shoe or boot" is c.1400. Down at heels (1732) refers to heels of boots or shoes worn down and the owner too poor to replace them. For Achilles' heel "only vulnerable spot" see Achilles. To "fight with (one's) heels" (fighten with heles) in Middle English meant "to run away."
"contemptible person," 1914 in U.S. underworld slang, originally "incompetent or worthless criminal," perhaps from a sense of "person in the lowest position" and thus from heel (n.1).
"to lean to one side," in reference to a ship, Old English hieldan "incline, lean, slope," from Proto-Germanic *helthijanan (cf. Middle Dutch helden "to lean," Dutch hellen, Old Norse hallr "inclined," Old High German halda, German halde "slope, declivity"). Re-spelled 16c. from Middle English hield, probably by misinterpretation of -d as a past tense suffix.
The rounded posterior portion of the foot under and behind the ankle.
A similar anatomical part, such as the rounded base of the palm.
[last sense fr heel, ''arm a fighting cock with a gaff or spur,'' found by 1755]
in anatomy, back part of the human foot, below the ankle and behind the arch, and the corresponding part of the foot in other mammals that walk with their heels touching the ground, such as the raccoon and the bear; it corresponds to the point of the hock of hoofed mammals and those that walk on their toes (e.g., horse, dog, cat). The contained tarsal bone, the calcaneus, appears first among the crocodilian reptiles; it was lost in birds by fusion with other tarsals and metatarsals but retained in mammals.