Depression - (noun)
(1) An emotional state that is characterised by sadness, low self-worth, and a feeling of hopelessness. (2) A long-term downturn in the economy. It is often defined as over two quarters (over six months) of negative growth.
Source: (1) Adapted from Encyclopedia Britannica (2) Adapted from Wikipedia
Example of Use: (1) Algorithms which can predict the likelihood of adult depression in employees are extremely dangerous. (2) The depression that Latvia suffered in the wake of the financial crisis was one of the heaviest in economic history.