Person generating much interest left Noah's rebuilt boat (4,5)
I believe the answer is:
loan shark
'person' is the definition.
(loan shark is a kind of person)
'left noah's rebuilt boat' is the wordplay.
'left' becomes 'l' (common abbreviation).
'rebuilt' indicates anagramming the letters.
'boat' becomes 'ark' (ark is a kind of boat).
'noahs' anagrammed gives 'oansh'.
'l'+'oansh'+'ark'='LOAN SHARK'
'generating much interest' is the link.
I am not very happy about this link. Some or all of it may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for loan shark that I've seen before include "Money lender" , "Usurer" , "One lends money at excessive rates of interest" , "Financial dealer" , "Unscrupulous moneylender (colloq.)" .)