Indomitable courage a feature of Educating Rita (4)
I believe the answer is:
grit
'indomitable courage' is the definition.
(I've seen this before)
'a feature of educating rita' is the wordplay.
'a feature of' indicates a hidden word.
'GRIT' can be found hidden inside 'educating rita'.
(Other definitions for grit that I've seen before include "lamb" , "Pluck; sand particles" , "Courage - clench - small particle of stone" , "Small hard particles - courage" , "Determination - which is found on winter roads" .)