Show charge orbiting an electron (8)
I believe the answer is:
indicate
'show' is the definition.
('indicate' can be a synonym of 'show')
'charge orbiting an electron' is the wordplay.
'charge' becomes 'indict' (indicting is a kind of charging).
'orbiting' means one lot of letters goes inside another.
'an' becomes 'a'.
'electron' becomes 'e' (abbreviation in physics).
'indict' going around 'a' is 'indicat'.
'indicat'+'e'='INDICATE'
(Other definitions for indicate that I've seen before include "Point out, make known" , "Point, show, signal" , "Point out, suggest" , "(Give a) signal" , "Point out or give some notion of" .)