### Clue: Trendy, like youth (7)
### Answer: INFANCY 
 ### Explanation: Definition: youth
  IN(trendy, as in the "in thing") + FANCY(like,wish to/for). 
Answer: One usually associates infancy with babies (as in "infants are not allowed in the theatre"), but no – it also means the period when you're still a minor in the eyes of the law, ranging from 14 years in Armenia to 21, with most countries including UK (except Scotland) stipulating it at 18, covering the youthful years.