Looks at powerless arthropods (7)
I believe the answer is:
insects
'arthropods' is the definition.
(insect is a kind of arthropod)
'looks at powerless' is the wordplay.
I cannot quite understand how this works, but
'at' could be 'in' (synonymous in some cases - eg at school, in school) and 'in' is found within the answer.
The remaining letters 'sects' is a valid word which might be clued in a way I don't see.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for insects that I've seen before include "Unimportant people" , "Bugs" , "crawlers, perhaps" , "Six-leggged creatures" , "Small invertebrate creatures" .)