Resistance stops bird moving herd (5)
I believe the answer is:
drove
'moving herd' is the definition.
(a drove is a herd of cattle being moved)
'resistance stops bird' is the wordplay.
'resistance' becomes 'r' (electronics abbreviation).
'stops' indicates putting letters inside.
'bird' becomes 'dove' (dove is a kind of bird).
'r' put inside 'dove' is 'DROVE'.
(Other definitions for drove that I've seen before include "took to the road" , "Incited" , "Moving flock; forced" , "Moving crowd" , "Carried along by force" .)