Synonyms for Youth (same or very similar meaning)
WordNet sense 1 (an early period of development):
early days
WordNet sense 2 (a young person (especially a young man or boy)):
younker, young person, spring chicken
WordNet sense 3 (young people collectively):
young
WordNet sense 4 (the freshness and vitality characteristic of a young person):
youthfulness, juvenility
From the ODE community, based on WordNet
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