Lost again badly, it brings wistful feelings (9)
I believe the answer is:
nostalgia
'wistful feelings' is the definition.
The definition and answer can be both feelings as well as being singular nouns.
Maybe you can see a link between them that I can't see?
'lost again badly' is the wordplay.
'badly' indicates an anagram (letters in the wrong order).
'lost'+'again'='lostagain'
'lostagain' anagrammed gives 'NOSTALGIA'.
'it brings' acts as a link.
Can you help me to learn more?
(Other definitions for nostalgia that I've seen before include "That may bring on homesickness" , "longing for home and family" , "Sentimental longing for the past" , "A longing for past times" , "Longing for what's gone" .)