Defn: Porosity. Wiseman.

PORISM
Po"rism, n. Etym: [Gr. porisme.]

1. (Geom.)

Defn: A proposition affirming the possibility of finding such conditions as will render a certain determinate problem indeterminate or capable of innumerable solutions. Playfair.

2. (Gr. Geom.)

Defn: A corollary. Brande & C.

Note: Three books of porisms of Euclid have been lost, but several attempts to determine the nature of these propositions and to restore them have been made by modern geometers.

PORISMATIC; PORISMATICAL
Po`ris*mat"ic, Po`ris*mat"ic*al, a.

Defn: Of or pertaining to a porism; poristic.

PORISTIC; PORISTICAL
Po*ris"tic, Po*ris"tic*al, a.Etym: [Gr.