- (of liquids) Density, thickness; the state or quality of being inspissated or thickened.
- 1803, Francis Bacon, The works of Francis Bacon, page 495:
- The cause is, for that it is over-moistened, and wanteth spissitude: and we have a merry saying, that they that go drunk to bed get daughters.
- 1849, American Journal of Pharmacy and the Sciences Supporting Public Health:
- When the juice of the poppy has been properly dried, that is rapidly, in a cool shade, and protected from dust, it possesses, at the spissitude of 70 per cent. (this is 30 of water) the following properties:...
- 1902, Technology Quarterly and Proceedings of the Society of Arts:
- The ratio between spissitude and percentage strength of solution varies, however, with the temperature, as shown by Figure 7, higher temperatures showing less increase in spissitude with increasing percentage strengths than is the case with low temperatures.
- Spiritual substance or density, viewed as the fourth dimension of an object.
- 1989, Amos Funkenstein, Theology and the Scientific Imagination from the Middle Ages to the Seventeenth Century, →ISBN:
- Bodies in and of themselves lack spissitude. But since, in nature, all bodies are permeated by spirit of some kind, the ability of a complex body to maintain its size indicates a certain, constant spissitude.
- 2012, S. Hutton, Henry More (1614–1687) Tercentenary Studies, →ISBN:
- The first concerns the peculiar attribute of spirit, its spissitude or spiritual density that fourth dimension which augments or diminishes as the spirit contracts or expands.
- 2012, E. A. Burtt, The Metaphysical Foundations of Modern Science, →ISBN:
- When the soul, for example, is contracted principally in the fourth ventricle, the space occupied possesses not only the three normal dimensions, but also this fourth dimension or spissitude.