Trap surrounded by enchantment is irresistible (8)
I believe the answer is:
magnetic
'irresistible' is the definition.
(thesaurus)
'trap surrounded by enchantment' is the wordplay.
'trap' becomes 'net' (net is a kind of trap).
'surrounded by' means one lot of letters goes inside another.
'enchantment' becomes 'magic' (I've seen this before).
'net' put inside 'magic' is 'MAGNETIC'.
'is' is the link.
(Other definitions for magnetic that I've seen before include "Having the property of attracting iron" , "Having the power to attract" , "Attracting iron or steel" , "attractive result" , "Able to attract metal, or charismatic" .)