A female, unable to walk, burning up (6)
I believe the answer is:
aflame
'burning up' is the definition.
(set on fire)
'a female unable to walk' is the wordplay.
'female' becomes 'f' (abbreviation).
'unable to walk' becomes 'lame' (I've seen this in another clue).
'a'+'f'+'lame'='AFLAME'
(Other definitions for aflame that I've seen before include "On fire" , "Deeply aroused" , "Ardent" , "Indicating excitement" , "Ablaze" .)