Sorrowful (3)
I believe the answer is:
sad
'sorrowful' is the definition.
(similar in meaning)
This is the entire clue.
(Other definitions for sad that I've seen before include "A form of depression in winter, initially" , "Unhappy or melancholy" , "Sorrowful, unhappy" , "Mournful - sorry" , "Gloomy" .)