Provide with Railway Union fund (5)
I believe the answer is:
'union fund' is the definition.
The definition and answer can be both related to property as well as being singular nouns.
Perhaps you can see an association between them that I can't see?
'provide with railway' is the wordplay.
'provide' becomes 'do' (do can mean to provide or serve up).
'with' becomes 'w' (abbreviation).
'railway' becomes 'ry' (abbreviation for railway).
Can you help me to learn more?
(Other definitions for dowry that I've seen before include "Rowdy (anag.)" , "Property bride brings" , "Money, property brought by a bride at marriage" , "Wealth brought by a bride" , "present for husband" .)