The Collaborative International Dictionary of English v.0.48:

Heredity \He*red"i*ty\, n. [L. hereditas heirship.] (Biol.)
   Hereditary transmission of the physical and psychical
   qualities of parents to their offspring; the biological law
   by which living beings tend to repeat their characteristics
   in their descendants. See Pangenesis.
   [1913 Webster]

WordNet (r) 3.0 (2006):

heredity
    n 1: the biological process whereby genetic factors are
         transmitted from one generation to the next
    2: the total of inherited attributes [syn: heredity, genetic
       endowment]