Definition:
Melancholic - A gloomy state of mind.


Example:
"At the end of the passable road they alighted, and for miles splashed on in silence through the terrible cypress woods where day never came. Ugly roots and malignant hanging nooses of Spanish moss beset them, and now and then a pile of dank stones or fragment of a rotting wall intensified by its hint of morbid habitation a depression which every malformed tree and every fungous islet combined to create."
-"The Call of Cthulhu" by H.P. Lovecraft


Explanation:
The setting is dark and gloomy. The woods are "terrible," the roots are "ugly," and the Spanish moss hangs in "nooses." It's all done to depress the reader, give an impression of a somber and terrible happening.