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

The juveniles were cited on suspicion of reckless driving and driving without a license, and the charges were forwarded to juvenile prosecutors, police said. — Madison Smalstig, Sacbee.com, 23 Sep. 2026

One of the tramps jumping off a freight car was the juvenile player, Frankie Darrow. — Thomas Doherty, HollywoodReporter, 19 Sep. 2026

Noun

Authorities searched throughout the evening for a missing juvenile before suspending recovery efforts overnight. — Kelsie Cairns , Michael Sinkewicz, FOXNews.com, 24 Sep. 2026

Two juveniles were cited after riding e-motorcycles through the Westfield Galleria mall Friday night, according to the Roseville Police Department. — Madison Smalstig, Sacbee.com, 23 Sep. 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