n.

1. 青春時代，青少年時期[U]
   I spent my youth in the country.

   我在鄉間度過了青少年時代。

2. （男）青年，小伙子[C]
   There are groups of youths playing basketball over there.

   那裡，一群群小伙子正在打籃球。

3. 青年們[the S][（+of）][G]
4. 年輕；朝氣；青春[U]
   My youth has gone.

   我的青春已不復存在。

5. 初期；早期[U]
   Cryonics is still in its youth.

   人體冷凍學還處於初始階段。

n.

1. the period between childhood and adult age.
   ▸the qualities of vigour, freshness, immaturity, etc. associated with being young.
2. [treated as sing. or pl.] young people.
   ▸a young man.