The Collaborative International Dictionary of English v.0.48:
Patriarchal \Pa`tri*ar"chal\, a. [Cf. F. patriarcal.]
1. Of or pertaining to a patriarch or to patriarchs;
possessed by, or subject to, patriarchs; as, patriarchal
authority or jurisdiction; a patriarchal see; a
2. Characteristic of a patriarch; venerable.
About whose patriarchal knee
Late the little children clung. --Tennyson.
3. (Ethnol.) Having an organization of society and government
in which the head of the family exercises authority over
all its generations.
Patriarchal cross (Her.), a cross, the shaft of which is
intersected by two transverse beams, the upper one being
the smaller. See Illust. (2) of Cross.
Patriarchal dispensation, the divine dispensation under
which the patriarchs lived before the law given by Moses.