An Italian cruise begins and ends the affair (7)
I believe the answer is:
romance
'affair' is the definition.
(I've seen this before)
'an italian cruise begins and ends the' is the wordplay.
'an italian' becomes 'roman' (Roman is an example**).
'begins' says to take the initial letters.
'and' is a charade indicator (letters next to each other).
'ends' indicates one should take the final letters.
The first letter of 'cruise' is 'c'.
The last letter of 'the' is 'e'.
'roman'+'c'+'e'='ROMANCE'
(Other definitions for romance that I've seen before include "Novel - love story" , "Novel (or often its main theme)" , "Lie" , "Court" , "Cameron (anag) - love story" .)