Son in scanty clothing — scanty, indeed (6)
I believe the answer is:
sparse
'clothing scanty indeed' is the definition.
I can't judge whether this defines the answer.
'son in scanty' is the wordplay.
'son' becomes 's' (genealogical abbreviation for son).
'in' means one lot of letters goes inside another.
'scanty' becomes 'spare' (synonyms).
's' put within 'spare' is 'SPARSE'.
(Other definitions for sparse that I've seen before include "rarely occurring" , "Thinly dispersed" , "Thin on the ground, scarce" , "Thinly dotted about" , "Rare" .)