(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"
clearly characterized or delimited; "lost in a maze of words both defined and undefined"; "each child has clearly defined duties"
clearly defined; "I have no formed opinion about the chances of success"
showing clearly the outline or profile or boundary; "hills defined against the evening sky"; "the setting sun showed the outlined figure of a man standing on the hill"