More current needs electricity with extra resistance initially (5)
I believe the answer is:
newer
'more current' is the definition.
('new' is associated in meaning with 'current')
'needs electricity with extra resistance initially' is the wordplay.
'initially' says to take the initial letters.
The first letters of 'needs electricity with extra resistance' is 'NEWER'.
(Other definitions for newer that I've seen before include "More current" , "Fresher, not as old" , "More recent" , "Fresher or more novel" , "More modern" .)