Gloomy yet funny linguistic study (9)
I believe the answer is:
etymology
'linguistic study' is the definition.
(I've seen this before)
'gloomy yet funny' is the wordplay.
'funny' indicates anagramming the letters.
'gloomy'+'yet'='gloomyyet'
'gloomyyet' is an anagram of 'ETYMOLOGY'.
(Other definitions for etymology that I've seen before include "Investigation of derivation of words" , "linguistic study" , "Word history" , "Word derivation" , "original source" .)