spring chicken 
noun
1 [usually with negative] informal A young person: you’re no spring chicken yourself any more...
- I'm no spring chicken any more but I feel fit as a fiddle.
- But in the past week, just about everything I have done has left me feeling middle-aged and I have finally had to admit to myself that I am no spring chicken.
- He wasn't old, but he was no spring chicken either.
2A young chicken for eating (originally available only in spring).The waitress consulted with a chef and said: ‘It's not free-range, but it's a spring chicken.’...
- For mains, Madame had the spring chicken with fries, while I went for the more traditional schnitzel.
- In Christian Europe, the slaughter was the beginning of the feasting season, which lasted until Lent - the fasting season - which ended with spring chicken and lamb and the first edible greens.