FIL'IAL, a. [L. filius, a son, flia, a daughter.]1. Pertaining to a son or daughter; becoming a child in relation to his parents. Filial love is such an affection as a child naturally bears to his parents. Filial duty or obedience is such duty or obedience as the child owes to his parents.2. Bearing the relation of a son.Springs of like leaf erect their filial heads.