The genetics and neurobiology of clinical depression have been well researched and are well defined. The term acedia is interesting from a historical standpoint and conforms most to reactionary depression. It is not a clinical diagnosis and I encourage you to avoid the implication it is an accepted medical condition. There are too many people with suicidal ideation who deserve the attention and care they need to escape the cycle of major depression that traps them and is most severe this time of year. Adding to the self diagnosed internet of confusion about major depression does not help!