youngster

n. youth, kid, child; young animal; young seaman (U.S. and British navies)

A child (plural: children) is primarily a boy or girl who has not reached puberty. However, some youth reach puberty earlier or later than expected. It is because of this, as well as the varying degrees of mental development, that a youth is often defined as a child by either psychological or chronological age rather than biological. The term also refers to offspring of any age; adults remain the children of their parents, no matter what their age. It can be applied to non-human offspring, as in the child node of a tree.
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Noun
1. a young person of either sex; "she writes books for children"; "they're just kids"; "`tiddler' is a British term for youngsters"
(synonym) child, kid, minor, shaver, nipper, small fry, tiddler, tike, tyke, fry, nestling
(hypernym) juvenile, juvenile person
(hyponym) bairn
(part-meronym) child's body

(n.)
A young person; a youngling; a lad.
  

hou4 qi3 zhi1 xiu4
An up-and-coming youngster.
A promising young person.