"Toska - noun /ˈtō-skə/ - Russian word roughly translated as sadness, melancholia, lugubriousness.
"No single word in English renders all the shades of toska. At its deepest and most painful, it is a sensation of great spiritual anguish, often without any specific cause. At less morbid levels it is a dull ache of the soul, a longing with nothing to long for, a sick pining, a vague restlessness, mental throes, yearning. In particular cases it may be the desire for somebody of something specific, nostalgia, love-sickness. At the lowest level it grades into ennui, boredom."
— Vladimir Nabokov
I share this with you because the word “Toska”reminds me largely of the feeling of depression. In fact, it is the embodiment of the feeling I have often felt myself. The way it is described here supersedes anything I could come up with. Therefore I simply copied and pasted the definition. The definition itself is, in a way, poetry. So I saw it fit to share here, on this site.