1. relating to or having the characteristics of a family - children of the same familial background - familial aggregation • Pertains to noun: family • Derivationally related forms: family 2. occurring among members of a family usually by heredity - an inherited disease - familial traits - genetically transmitted features • Syn: genetic, hereditary, inherited, transmitted, transmissible • Similar to: inheritable, heritable • Derivationally related forms: transmit (for: transmissible), heredity (for: hereditary), family