No side backs light inventor (6)
I believe the answer is:
edison
'light inventor' is the definition.
'edison' can be an answer for 'inventor' (Edison is an example). I am not certain of the 'light' bit.
'no side backs' is the wordplay.
'backs' says the letters should be written backwards (I've seen 'back' mean this).
'no'+'side'='noside'
'noside' in reverse letter order is 'EDISON'.
Can you help me to learn more?
(Other definitions for edison that I've seen before include "US inventor of over 1,000 devices" , "Onside with great American inventor" , "scientist" , "No side to this american inventor" , "Inventor of the light bulb" .)