### Clue: One day isles to the west, rejecting society, become peaceful (7)
### Answer: IDYLLIC 
 ### Explanation: Definition: peaceful
 I(Roman numeral for "one") + D(abbrev. for "day") + **reversal of**(… to the west, in an across clue) "Scilly"(Isles of, an archipelago off the south-western tip of Cornwall) **minus**(rejecting) "s"(abbrev. for "society").