Nautical chairman? (5)
I believe the answer is:
bosun
'nautical chairman?' is the definition.
The definition and answer can be both people as well as being singular nouns.
Perhaps you can see an association between them that I don't see?
This is all the clue.
Can you help me to learn more?
(Other definitions for bosun that I've seen before include "Bonus for a small boatswain" , "Petty officer on a merchant ship" , "An abbreviated boatswain" , "Ship's officer in charge of equipment and crew" , "A short boatswain" .)