Crenation refers to the process or condition in which a cell shrinks and develops a notched or scalloped edge, typically as a result of losing water through osmosis when placed in a hypertonic solution. It can also refer more generally to the formation of a notched or indented edge on an object, such as a coin or a leaf. In biology, crenation is specifically associated with red blood cells and their response to changes in osmotic pressure.
