Learner's definition of DEPRESSION
1 a : a state of feeling sad b : a serious medical condition in which a person feels very sad, hopeless, and unimportant and often is unable to live in a normal way
She has been undergoing treatment for severe/deep depression.
Many people suffer from clinical depression for years before being diagnosed.
bouts/periods of depression
2 : a period of time in which there is little economic activity and many people do not have jobs
After several years of an economic boom, it looks as though we may be heading toward a depression.
He grew up during the (Great) Depression. [=the 1930s, when the U.S. and many other countries were in a very bad depression]
3 [count] : an area on a surface that is lower than other parts : a low spot 4 [count], weather : a large area where there is low pressure in the atmosphere with usually clouds and rain