It has a steadying influence at sea (4)
I believe the answer is:
keel
'it has a steadying influence at sea' is the definition.
The definition suggests a singular noun which matches the answer.
'it' is the wordplay.
I cannot quite understand how this works, but
'it' could be 'e' ('e' can mean 'electronic' which is similar to 'IT') and 'e' is located in the answer.
The remaining letters 'kel' is a valid word which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for keel that I've seen before include "Main longitudinal beam of a vessel's the hull" , "Cool, or it used to be" , "ridge" , "Structure along base of ship" , "Ship's basic longitudinal structure" .)