no spring chicken
slang No longer young or youthful. (A "spring chicken" refers to a young chicken.) I'm no spring chicken, so I can't stay out till 2 AM drinking and dancing anymore.
no (spring) chickennot a young person. euphemistic
2005 Molly Hart Road to Ruination She must've been in at least her mid-forties, she was no spring chicken, but she looked good for her age.