Split money invested in a wealthy person (5)
I believe the answer is:
halve
'split' is the definition.
(thesaurus)
'money invested in a wealthy person' is the wordplay.
'money' becomes 'l' (L can mean 'pounds').
'invested in' means one lot of letters goes inside another.
'a wealthy person' becomes 'have' ('have' can be a synonym of 'wealthy person'**).
'l' going inside 'have' is 'HALVE'.
(Other definitions for halve that I've seen before include "Bisect" , "Divide equally between two" , "Share equally" , "cut by fifty percent" , "split 50/50" .)