Density fluctuation refers to the variations in density within a liquid, where the actual density at a point can differ from the average density. Hydrogen bonding in water enhances these fluctuations by creating temporary structures that lead to localized density changes. The presence of hydrogen bonds allows for dynamic interactions between water molecules, contributing to the non-uniform density distribution. Understanding these fluctuations is crucial for comprehending various physical properties of liquids. Overall, hydrogen bonding plays a significant role in the behavior of density fluctuations in water.