The Collaborative International Dictionary
Spissitude
Spissitude \Spis"si*tude\, n. [L. spissitudo.]
The quality or state of being spissated; as, the spissitude
of coagulated blood, or of any coagulum.
--Arbuthnot.
Douglas Harper's Etymology Dictionary
spissitude
"density, thickness, compactness," mid-15c., from Latin spissitudo "thickness, density," from spissus "thick, dense, compact, close" (source of Italian spesso, Spanish espeso, Old French espes, French épais). Related: Spissated.
Wiktionary
spissitude
n. density, thickness; the state or quality of being inspissated, thickened (used of liquids)