Nick disheartened in beer joint (5)
I believe the answer is:
ankle
'joint' is the definition.
(joint of the body)
'nick disheartened in beer' is the wordplay.
'disheartened' says to hollow out the word (remove centre letters).
'in' indicates putting letters inside.
'beer' becomes 'ale' (type of beer).
'nick' with its centre removed is 'nk'.
'nk' going inside 'ale' is 'ANKLE'.
(Other definitions for ankle that I've seen before include "Bone over foot" , "Lower leg joint" , "Part of the leg between the foot and the shin" , "Major joint in lower limb" , "Location of the talus" .)