Do a turn at the helm perhaps (4)
I believe the answer is:
veer
'do' is the definition.
The definition and answer can be both to do with motion as well as being verbs in their base form.
Maybe you can see a link between them that I can't see?
I don't understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for veer that I've seen before include "Change direction sharply" , "Change direction abruptly" , "Change direction or course, like wind" , "Turn sharply" , "Suddenly change direction" .)