Less difficult (6)
'less difficult' is the definition.
('easy' can be the opposite of 'difficult' so perhaps 'easier' is reasonable for 'less difficult')
This is all the clue.
(Other definitions for easier that I've seen before include "More facile" , "Less burdensome" , "More comfortable or less difficult" , "Simpler" , "more like a piece of cake" .)
(Other definitions for simpler that I've seen before include "That wasn't so hard!)" , "More easy" , "Less complicated or complex" , "Easier" .)