Blokes absorbed by plug change (5)
I believe the answer is:
amend
'change' is the definition.
(amending is a kind of changing)
'blokes absorbed by plug' is the wordplay.
'blokes' becomes 'men' (I've seen this in other clues).
'absorbed by' is an insertion indicator.
'plug' becomes 'ad' (Advertisement plugs products).
'men' put inside 'ad' is 'AMEND'.
(Other definitions for amend that I've seen before include "Rectify" , "Change to improve" , "Modify - edit" , "Alter in detail" , "Corrct error, make a minor aleration" .)