Notable experience swimming so deep around island (7)
I believe the answer is:
episode
'notable experience' is the definition.
'episode' can be an answer for 'experience' (thesaurus). I'm not sure about the 'notable' bit.
'swimming so deep around island' is the wordplay.
'swimming' indicates an anagram (letters swim around into a new order).
'around' means one lot of letters goes inside another.
'island' becomes 'i' (geographical abbreviation).
'so'+'deep'='sodeep'
'sodeep' with letters rearranged gives 'epsode'.
'epsode' placed around 'i' is 'EPISODE'.
Can you help me to learn more?
(Other definitions for episode that I've seen before include "Part of TV series" , "Instalment of a TV series" , "Chapter or event" , "One instalment of a series" , "Instalment; incident" .)