Meagre, filthy home's outside toilet (6)
I believe the answer is:
scanty
'meagre' is the definition.
(similar in meaning)
'filthy home's outside toilet' is the wordplay.
'filthy home' becomes 'sty'.
'outside' indicates putting letters inside (some letters go outside others).
'toilet' becomes 'can' (synonyms).
'sty' going around 'can' is 'SCANTY'.
(Other definitions for scanty that I've seen before include "Meagre, deficient" , "Spare" , "Insufficient in amount" , "Give (to a good cause)" , "Sparse, meagre" .)