noun.
Extreme, persistent sadness or hopelessness; depression. No longer in clinical use.
The Century Dictionary and Cyclopedia
noun.
In pathology, a mental condition characterized by great depression combined with a sluggishness and apparent painfulness of mental action.
noun.
Same as melancholy, 2.
the GNU version of the Collaborative International Dictionary of English
noun.
A kind of mental unsoundness characterized by extreme depression of spirits, ill-grounded fears, delusions, and brooding over one particular subject or train of ideas.