1530s, from Middle French hérédité (12c.), from Latin hereditatem (nominative hereditas) "heirship, inheritance, condition of being an heir," from heres (genitive heredis) "heir, heiress," from PIE root *ghe- "to be empty, left behind" (cf. Greek khera "widow"). Legal sense of "inheritable quality or character" first recorded 1784; the modern biological sense seems to be found first in 1863, introduced by Herbert Spencer.
heredity he·red·i·ty (hə-rěd'ĭ-tē)
n.
The genetic transmission of characteristics from parent to offspring.
One's genetic constitution.