Stop old women's grant (5)
I believe the answer is:
endow
'grant' is the definition.
(thesaurus)
'stop old women's' is the wordplay.
'stop' becomes 'end' ('end' can be a synonym of 'stop'**).
'old' becomes 'o' (common abbreviation eg in OE for Old English).
'women' becomes 'w'.
'end'+'o'+'w'='ENDOW'
(Other definitions for endow that I've seen before include "Provide capital to ensure an income for an institution" , "Settle permanent income on" , "Bequeath or give an income or property to" , "Bequeath estate to" , "Give qualities or abilities to" .)