At sea, can keep crews moving (5)
I believe the answer is:
screw
'at sea can keep' is the definition.
I can't judge whether this definition defines the answer.
'crews moving' is the wordplay.
'moving' is an anagram indicator (letters are moved around).
'crews' is an anagram of 'SCREW'.
Can you help me to learn more?
(Other definitions for screw that I've seen before include "Archimedes' invention" , "con" , "may need a driver" , "Fastener, rivet" , "Bring pressure to bear" .)