The basic requirement for a live wire (7)
I believe the answer is:
element
'the basic' is the definition.
(I've seen this before)
I cannot understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for element that I've seen before include "Primary chemical substance" , "Chemical building-block" , "Singular ingredient" , "Component - factor" , "Eg copper" .)