The degree to which a refractive medium retards transmitted rays of light.
- ‘For each sample, the optical densities were plotted as a function of volume loaded.’
- ‘The second method comprised measuring optical densities of bacterial cultures.’
- ‘The physical density is changed, but is the optical density changed as well?’
- ‘Cultures were grown to an optical density of 1.0 in rich medium containing 2% dextrose.’
- ‘The antioxidant potential of serum was calculated by the decrease in the optical density during the first minute.’