青壯年

青壮年
qīngzhuàngnián
the prime of one's life

CEDICT

young age and “prime age”; prime time of one's life; age defined variously as between 15 and 64, between 15 and 60, or between 30 and 40

Wiktionary

Entry Composition

1 青 qīng
  1. green
  2. blue
  3. black
  4. youth
  5. young (of people)
2 壯年 zhuàngnián
  1. lit. robust years
  2. prime of life
  3. summer
  4. able-bodied (fit for military service)
  5. mature (talent, garden etc)

Related entries

春秋鼎盛 chūnqiūdǐngshèng the prime of one's life
盛年 shèngnián the prime of one's life
英年 yīngnián
  1. the prime of one's life
  2. youthful years