A little beneath one, young love (5)
I believe the answer is:
honey
'love' is the definition.
('honey' can be a synonym of 'love')
'a little beneath one young' is the wordplay.
'a little' indicates a hidden word.
'HONEY' can be found hidden inside 'beneath one young'.
(Other definitions for honey that I've seen before include "Beloved" , "Hive fluid" , "Love" , "sweetener" , "Sweet term of endearment" .)