What does "reform school" mean?

A penal institution for juveniles, especially males.

Reform school

Common synonyms include: bastille, black hole, borstal, borstal institution, borstal school, bridewell.

noun

noun ·Rare ·Advanced level

Noun

1
A penal institution for juveniles, especially males. dated
"And through this one small error of judgment, Elwood’s life is changed when he is sent to a reform school called Nickel."
2
correctional institution for the detention and discipline and training of young or first offenders wordnet

"And through this one small error of judgment, Elwood’s life is changed when he is sent to a reform school called Nickel."