Take pirate's cap (4)
I believe the answer is:
kepi
'cap' is the definition.
(kepi is a kind of cap)
'take pirate's' is the wordplay.
'KEPI' is hidden within the letters.
But, I'm not sure how the hidden word is indicated.
Can you help me to learn more?
(Other definitions for kepi that I've seen before include "French army cap" , "French military headgear" , "What French soldier may assume" , "Flat-topped military cap" , "French military hat" .)