absorption coefficient: a measure of the rate of decrease in the intensity of electromagnetic radiation (as light) as it passes through a given substance; the fraction of incident radiant energy absorbed per unit mass or thickness of an absorber
coefficient: a constant number that serves as a measure of some property or characteristic
shimchath torah: (Judaism) a Jewish holy day celebrated on the 22nd or 23rd of Tishri to celebrate the completion of the annual cycle of readings of the Torah