A cursory hug on entering, not from love (6)
I believe the answer is:
nought
'love' is the definition.
(I've seen this before)
'a cursory hug on entering not' is the wordplay.
'a cursory hug' becomes 'ugh' (I can't justify this - if you can you should believe this answer much more).
'on entering' indicates putting letters inside.
'ugh' going within 'not' is 'NOUGHT'.
'from' acts as a link.
Can you help me to learn more?
(Other definitions for nought that I've seen before include "Go hunt for nothing" , "Love" , "Zilch" , "The figure 0" , "The digit 0" .)