Osmosensitivity is the ability of an organism or cell to respond to changes in the concentration of fluids or solutes. There are several synonyms for this term, including osmoregulation, osmoreception, osmoregulatory, and osmotic. Osmoregulation refers to the process by which an organism adjusts its internal fluids to maintain a stable environment in the face of external changes in pressure or concentration. Osmoreception refers to the detection of changes in salt concentration by specialized receptors in the body. Osmoregulatory mechanisms help organisms to maintain steady internal conditions despite varying external conditions. Finally, osmotic refers to the process by which fluids or solutes move across a semi-permeable membrane. Synonyms for osmosensitivity are essential in understanding the complex processes that organisms use to adapt to changing environments.