Possibly glib letter from an old seaman (5)

I believe the answer is:

bligh

I'm a little stuck... Click here to teach me more about this clue!

'an old seaman' is the definition.
The definition suggests a singular noun which matches the answer.

'possibly glib letter' is the wordplay.
'possibly' indicates anagramming the letters.
'letter' becomes 'h' (**).
'glib' anagrammed gives 'blig'.
'blig'+'h'='BLIGH'

'from' is the link.

Can you help me to learn more?

(Other definitions for bligh that I've seen before include "Vice admiral" , "HMS Bounty captain" , "CA [CHILDRENS ADVENTURE] captain" , "The mutinous Bounty's captain" , "old captain dismissed" .)

I've seen this clue in the Evening Standard.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.