(chemistry) a process in which one substance permeates another; a fluid permeates or is dissolved by a liquid or solid
(physics) the process in which incident radiated energy is retained without reflection or transmission on passing through a medium; "the absorption of photons by atoms or molecules"
a constitutional tendency to be gloomy and depressed
characterized by or causing or expressing sadness; "growing more melancholy every hour"; "her melancholic smile"; "we acquainted him with the melancholy truth"