What does endosmotic mean?
Endosmotic is an adjective used in physiology and physical chemistry to describe processes involving endosmosis — the inward flow of water or another fluid through a semipermeable membrane, moving from a dilute solution toward one of higher concentration. When a cell placed in fresh water swells because water is drawn across its membrane, that movement can be described as endosmotic. The word was introduced in the nineteenth century by the French physiologist Henri Dutrochet, who coined 'endosmose' and 'exosmose' to distinguish the two directions of osmotic transfer. Today it survives mainly in older scientific literature and specialized discussions of membrane phenomena, having largely given way to the broader adjective 'osmotic'. Its enduring counterpart, 'exosmotic', denotes the opposite, outward-directed flow.
adjectiveRelating to or involving endosmosis, the inward flow of a fluid through a semipermeable membrane from a region of lower to higher solute concentration.
- Relating to endosmosis: the passage of a fluid inward through a semipermeable membrane toward a solution of higher concentration.
"The endosmotic movement of water into the cell caused it to swell visibly under the microscope."
"The egg swelled as endosmotic action drew water through its membrane into the syrup-free interior."
"Dutrochet's early experiments on endosmotic currents helped establish the foundations of modern membrane theory."
Before the word 'osmosis' even existed, scientists were already describing its inward half — endosmose — coined by a French physiologist studying how fluids creep through membranes.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of endosmotic
Endosmotic derives from endosmosis, a term coined in the 1820s by French physiologist Henri Dutrochet as 'endosmose', combining Greek 'endo-' (within) with 'ōsmos' (impulse, thrust). English adopted the adjective form alongside the noun, mirroring Dutrochet's paired coinage 'exosmose'. The shorter word 'osmosis' itself was formed later in the nineteenth century from the same Greek root.
Related word forms
How endosmotic is actually used
A technical term confined almost entirely to scientific and historical writing on physiology and membrane transport. In modern biology, 'osmotic' has largely displaced it, since direction of flow is usually stated separately.
Easily confused with endosmotic
Endosmotic describes inward diffusion through a membrane toward a more concentrated solution, while exosmotic describes outward diffusion away from it.