juvenile

1 of 2

adjective

ju·​ve·​nile ˈjü-və-ˌnī(-ə)l  -nᵊl 

1

: physiologically immature or undeveloped : young

juvenile birds

2

a

: of, relating to, characteristic of, or suitable for children or young people

juvenile fiction

b

: of or relating to young people who have committed or are accused of committing a criminal offense

the juvenile justice system

juvenile crime

3

: reflecting psychological or intellectual immaturity : childish

juvenile behavior

juvenile pranks

told him he was being juvenile

4

: derived from sources within the earth and coming to the surface for the first time

—used especially of water and gas

juvenile

2 of 2

noun

plural juveniles

1

a

: a young person : youth

often, specifically : an individual who is under an age fixed by law (such as 18 years) at which a person would be charged as an adult for a criminal act

… some states also have been changing their laws to give school administrators more access to the records of juveniles whose cases were processed by juvenile courts.

—Peter Schmidt

b

: a book for children or young people

2

: a young individual resembling an adult of its kind except in size and reproductive activity: such as

a

: a fledged bird not yet in adult plumage

b

: a 2-year-old racehorse

3

: an actor or actress who plays youthful parts

Synonyms of juvenile

Adjective

• young
• immature

Noun

• kid
• child

Examples of juvenile in a Sentence

Adjective

She criticized his juvenile behavior at the party.

a juvenile alligator just hatched from its egg

Noun

She works to keep juveniles away from drugs.

a medical study that followed juveniles through adolescence and into adulthood

Recent Examples on the Web

Adjective

But the 18 young mothers served through Citrus’ child welfare contract do not qualify for that program because they are not involved with the court system through probation, post-commitment supervision or other juvenile justice pathways. — Miami Herald, 24 July 2026

After the impact, a juvenile orca is seen eating some of the smaller pieces of the fish, while the adults eat from the remaining carcass. — Matthew Glasser, ABC News, 23 July 2026

Noun

One of the first incidents that year was a brawl involving about 50 juveniles, police at the time said, with a gunshot heard later that night, according to previous Sacramento Bee reporting. — Corey Schmidt, Sacbee.com, 26 July 2026

The suspect, who is not being identified due to his status as a juvenile, is accused of firing multiple shots from a handgun. — Clara Harter, Los Angeles Times, 24 July 2026

Word History

Etymology

Adjective

French or Latin; French juvénile, from Latin juvenilis, from juvenis young person — more at young

First Known Use

Adjective

1625, in the meaning defined at sense 1

Noun

1733, in the meaning defined at sense 1a

Phrases Containing juvenile

• juvenile court
• juvenile delinquency
• juvenile diabetes
• juvenile hormone
• juvenile officer
• juvenile-onset diabetes

Kids Definition

juvenile

1 of 2 adjective

ju·​ve·​nile ˈjü-və-ˌnīl  -vən-ᵊl 

1

: showing incomplete development : immature, childish

2

: of, relating to, or characteristic of children or young people

juvenility

ˌjü-və-ˈnil-ət-ē

noun

juvenile

2 of 2 noun

1

: a young person, animal, or plant

2

: a book for young people

3

: an actor who plays youthful parts

Medical Definition

juvenile

1 of 2 adjective

ju·​ve·​nile ˈjü-və-ˌnīl  -vən-ᵊl 

1

: physiologically immature or undeveloped

juvenile fish

2

: of, relating to, characteristic of, or affecting children or young people

juvenile arthritis

3

: reflecting psychological or intellectual immaturity

juvenile behavior

juvenile

2 of 2 noun

1

: a young person

especially : one below the legally established age (as of 18) of adulthood

2

: a young individual resembling an adult of its kind except in size and reproductive activity

Legal Definition

juvenile

noun

ju·​ve·​nile

ˈjü-və-ˌnīl, -nəl

: an individual who is under an age fixed by law (as 18 years) at which he or she would be charged as an adult for a criminal act compare minor