Head of ITV rejected a pitch: 'Love Island Lover' (9)
I believe the answer is:
inamorata
'lover' is the definition.
(I've seen this before)
'head of itv rejected a pitch love island' is the wordplay.
'head of' suggests taking the first letters.
'rejected' says the letters should be written in reverse.
'pitch' becomes 'tar' (synonyms).
'love island' becomes 'oman' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
The initial letter of 'itv' is 'i'.
'a'+'tar'+'oman'='ataroman'
'ataroman' backwards is 'namorata'.
'i'+'namorata'='INAMORATA'
Can you help me to learn more?
(Other definitions for inamorata that I've seen before include "Sweetheart" , "Woman beloved" , "Woman in love" , "Girlfriend" , "6 across [BOSOM] friend" .)