Weak heartless guy whose name escapes me (6)
I believe the answer is:
thingy
'name escapes me' is the definition.
I know nothing about this answer so I can't tell whether it can be defined by this definition.
'weak heartless guy' is the wordplay.
'weak' becomes 'thin' (similar in meaning).
'heartless' means to remove the middle letters.
'guy' with its centre taken out is 'gy'.
'thin'+'gy'='THINGY'
'whose' is the link.
Can you help me to learn more?
(Other definitions for thingy that I've seen before include "What's-its-name - nighty (anag)" , "I forget his name" , "whose name can't be remembered" .)