Go after half of Ruth's money (5)
I believe the answer is:
rupee
'money' is the definition.
(currency of India)
'go after half of ruth's' is the wordplay.
'go' becomes 'pee' (both can mean to urinate**).
'after' means one lot of letters go next to another.
'half of' means to take half the letters.
'ruth' halved is 'ru'.
'pee' put after 'ru' is 'RUPEE'.
(Other definitions for rupee that I've seen before include "little money abroad" , "Currency of India, Pakistan and Bhutan" , "cash" , "low cost in Pakistan?" , "foreign currency" .)