Poor maiden before stealing silver (6)
I believe the answer is:
meagre
'poor' is the definition.
(I've seen this before)
'maiden before stealing silver' is the wordplay.
'maiden' becomes 'm' (cricket abbreviation).
'before' becomes 'ere' (poetic term for 'before').
'stealing' means one lot of letters goes inside another.
'silver' becomes 'Ag' (Ag is the chemical symbol for silver).
'ere' placed around 'ag' is 'eagre'.
'm'+'eagre'='MEAGRE'
(Other definitions for meagre that I've seen before include "Lacking in quantity/quality" , "Sparse" , "little" , "Lean and scanty" , "Insufficient; scanty" .)