Allowing plastic bag in new London emporium initially (8)
I believe the answer is:
enabling
'allowing' is the definition.
'plastic bag in new london emporium initially' is the wordplay.
'plastic' indicates an anagram (plastic can mean easily moulded).
'initially' indicates taking the first letters.
The first letters of 'new london emporium' is 'nle'.
'bag'+'in'+'nle'='baginnle'
'baginnle' is an anagram of 'ENABLING'.
(Other definitions for enabling that I've seen before include "Authorising" , "Giving authority or means to do something" , "Being permissive" , "Empowering" , "Making something possible, facilitating" .)