kid vs army brat

kid and army brat both are nouns.

Word	Noun	Adjective	Verb	Adverb
kid	Yes	No	Yes	No
army brat	Yes	No	No	No

As nouns, army brat is a hyponym of kid; that is, army brat is a word with a more specific, narrower meaning than kid:

Other hyponyms of kid include babe, baby, infant, female offspring, male offspring, man-child, stepchild.

kid (noun)	army brat (noun)
young goat	the child of a career officer of the United States Army
a young person of either sex
a human offspring (son or daughter) of any age
soft smooth leather from the hide of a young goat

kid (verb)	army brat (verb)
be silly or tease one another
tell false information to for fun