What is "kosmotropic"

a. (context physics chemistry English) Describing ions (normally small, with a high charge density) that stabilize intermolecular interactions in water, especially by stabilizing hydrogen bonds

Co-solvents (in water solvent) are defined as kosmotropic (order-making) if they contribute to the stability and structure of water-water interactions. Kosmotropes cause water molecules to favorably interact, which also (in effect) stabilizes intramolecular interactions in macromolecules such as proteins. Chaotropic agents (disorder-makers) have the opposite effect, disrupting water structure, increasing the solubility of nonpolar solvent particles, and destabilizing solute aggregates.