'Hop it,' I fulminated, putting in 'sorry!' (7)
I believe the answer is:
pitiful
'sorry' is the definition.
(I know that sorry can be written as pitiful)
'hop it i fulminated putting in' is the wordplay.
'in' indicates a hidden word.
'PITIFUL' is hidden in the letters of 'hop it i fulminated putting'.
(Other definitions for pitiful that I've seen before include "base" , "Miserable" , "Sad - wretched" , "Distressing" , "Arousing feeling of sorrow, lamentable" .)