Besaiel \Be*saiel"\, Besaile \Be*saile"\, Besayle \Be*sayle"\, n. [OF. beseel, F. bisa["i]eul, fr. L. bis twice + LL. avolus, dim. of L. avus grandfather.] 1. A great-grandfather. [Obs.] 2. (Law) A kind of writ which formerly lay where a great-grandfather died seized of lands in fee simple, and on the day of his death a stranger abated or entered and kept the heir out. This is now abolished. --Blackstone.