Charm a chap with temptation (6)
I believe the answer is:
allure
'charm' is the definition.
(I've seen this before)
'a chap with temptation' is the wordplay.
'a chap' becomes 'al' (**).
'with' means one lot of letters go next to another.
'temptation' becomes 'lure' (lure is a kind of temptation).
'al'+'lure'='ALLURE'
(Other definitions for allure that I've seen before include "Enticement, attraction" , "Power to attract by personal charm" , "Glamorous appeal" , "There's glamour" , "Seduction" .)