Collected head of state in navy vessel at sea (9)
I believe the answer is:
nerveless
'collected' is the definition.
Both the answer and definition are adjectives. Perhaps there's an association between them I don't understand?
'head of state in navy vessel at sea' is the wordplay.
'head of state' becomes 'ER' (abbreviation for Elizabeth Regina).
'in' means one lot of letters goes inside another.
'navy' becomes 'N' (common abbreviation eg in RN Royal Navy).
'at sea' indicates anagramming the letters.
'n'+'vessel'='nvessel'
'nvessel' with letters rearranged gives 'nveless'.
'er' put within 'nveless' is 'NERVELESS'.
Can you help me to learn more?
(Other definitions for nerveless that I've seen before include "Feeble" , "Having great confidence" , "Showing calm self-control" , "calm and collected" , "Not able to feel" .)