Shelter hags giving up silver for tithes (6)
I believe the answer is:
tenths
'tithes' is the definition.
(I've seen this before)
'shelter hags giving up silver' is the wordplay.
'shelter' becomes 'tent' (canvas shelter).
'giving up' indicates named letters should be taken away.
'silver' becomes 'Ag' (Ag is the chemical symbol for silver).
'hags' with 'ag' taken away is 'hs'.
'tent'+'hs'='TENTHS'
'for' is the link.
(Other definitions for tenths that I've seen before include "tiny portions" , "Small portions" , "Tithes" , "Sections" .)