prebleach adjective 1verb 1forms 3 adjective1 •Before a bleaching operation.Right panels represent the time-course of a FRAP experiment: prebleach image (top), first image after bleach (middle), 100 s after start of acquisition (bottom). — 2015 verb1 •To apply a bleaching operation in advance of further bleaching.Since this autofluorescence component bleaches rapidly, we deliberately prebleach it before starting the experiment. — 2012 formsprebleached · prebleaching · prebleaches