Part of somebody's Seychelles journey (7)
I believe the answer is:
odyssey
'journey' is the definition.
(odyssey is a kind of journey)
'part of somebody's seychelles' is the wordplay.
'part of' indicates a hidden word.
'ODYSSEY' is hidden in the letters of 'somebodys seychelles'.
(Other definitions for odyssey that I've seen before include "Homerian epic" , "Significant journey (by Homer?)" , "Homer's epic poen about great journey" , "A long adventurous journey - see Homer" , "'Long eventful journey, such as that of Ulysses (7)'" .)