Youth leader leaves catalogue to originator (8)
I believe the answer is:
inventor
'to originator' is the definition.
(thesaurus)
'youth leader leaves catalogue' is the wordplay.
'youth leader' becomes 'y' (I've seen this in other clues).
'leaves' indicates named letters should be taken away.
'catalogue' becomes 'inventory' (both can mean a list of items).
'inventory' with 'y' removed is 'INVENTOR'.
(Other definitions for inventor that I've seen before include "Creator of something new" , "He discovers" , "Eg, Edison" , "Bell, perhaps" , "Creator, first to make something" .)