Heard first person on ship get cosmetic (8)
I believe the answer is:
eyeliner
'cosmetic' is the definition.
(I've seen this before)
'heard first person on ship' is the wordplay.
'heard' shows a homophone (sound like).
'first person' becomes 'I' (first-person pronoun).
'on' is a charade indicator (letters next to each other).
'ship' becomes 'liner' (as in an ocean liner).
'i' is a homophone of 'eye'.
'eye'+'liner'='EYELINER'
'get' is the link.
(Other definitions for eyeliner that I've seen before include "Dark marks left by this" , "Item of 25dn" , "kind of cosmetic" , "Make-up item" , "instrument for enhancing lamps" .)