† firmaˈmentary,a.Obs.rare. [f. as prec. +-ary.] =prec. 1633T. Adams Exp. 2 Peter ii. 7 Some by that firmamentary division of the waters, have dreamt of a watery heaven above the stars.1690Boyle Chr. Virtuoso i. 69 And much more must they do so..who believe..there were..Firmamentary comets.