SINCE 1828

An Encyclopædia Britannica Company

1

grown-up

play

adjective \ ˈgrōn-ˌəp \

Definition of grown-up

1 :not childish or immature :adult

2 :of, for, or characteristic of adults

insisted on wearing grown-up clothes

See grown-up defined for English-language learners

See grown-up defined for kids

First Known Use of grown-up

1633

grown-up Synonyms

Synonyms

grown-up, mature

Antonyms

adolescent, immature

Near Antonyms

childish, infantile, kiddish

2

grown-up

noun

Definition of grown-up

:adult

See grown-up defined for English-language learners

First Known Use of grown-up

1813

grown-up Synonyms

Synonyms

grown-up

Related Words

middle-ager; ancient, elder, gaffer, graybeard, oldster, old-timer, senior, senior citizen

Near Antonyms

bairn [chiefly Scottish], child, cub, kid, moppet, tad, toddler, tot, tyke (also tike); baby, infant; adolescent, juvenile, minor, youngling, youngster, youth; preteen, preteen-ager, teen, teenager, teener, teenybopper, tween

GROWN-UP Defined for English Language Learners

grown-up

play

adjective

Definition of grown-up for English Language Learners

: no longer young : fully grown
: suitable for adults
: like an adult

grown-up

noun

Definition of grown-up for English Language Learners

: a person who is fully grown

GROWN-UP Defined for Kids

1

grown-up

adjective \ ˈgrōn-ˌəp \

Definition of grown-up for Students

:¹adult

2

grown-up

noun

Definition of grown-up for Students

:an adult person

Learn More about grown-up

See words that rhyme with grown-up Thesaurus: All synonyms and antonyms for grown-up Nglish: Translation of grown-up for Spanish speakers Britannica English: Translation of grown-up for Arabic speakers

Seen and Heard

What made you want to look up grown-up? Please tell us where you read or heard it (including the quote, if possible).

show

WORD OF THE DAY

anathematize

play

to curse or denounce

BROWSE DICTIONARY

growly

grown

grown-up

grown-upness

grow on

Test Your Vocabulary

Merriam-Webster's New Words Quiz—Fall 2017 Edition!

Which of the following is a new sense of the word bunny?

Test your knowledge - and maybe learn something along the way.

TAKE THE QUIZ

Word Winder's CrossWinder

Test Your Knowledge - and learn some interesting things along the way.

TAKE THE QUIZ

Words at Play

alt-59c52d6ee2f72

Breathing Life Into 'Inspire'

The word's origins are quite literal

alt-59c4207ecf106

Let's Talk 'Tea'

Spill it, sip it: just make it hot.

8 Words and Phrases from Boxing and Wrestling

Common terms that come from boxing and wrestling

alt-59c2960017c94

The Ambiguity of Pushing 'Up' and 'Back'

When you push a meeting, where does it go?

Ask the Editors

video-title-words-of-the-year-1066

Words of the Year: 1066

Or, Why Pig Meat is Called 'Pork' and Cow Meat is Called 'Beef'

How Often Is 'Biweekly'?

Don't get us started on 'bimonthly'

video-irregardless-grammar-peeve-blend-of-the-synonyms-irrespective-and-regardless

Irregardless

It is in fact a real word (but that doesn't mean you should use it).

video-moose-goose-weird-plurals

Weird Plurals

One goose, two geese. One moose, two... moose. What's up with that?

Word Games

young-plant-shoots

Merriam-Webster's New Words Quiz—Fall 2017 Edition!

You're going to have to memorize the dictionary again.

Take the quiz

stylized-drawing-of-woman-pole-vaulting-across-gap-to-get-trophy

Challenging Vocabulary Quiz Returns!

No tricks, just difficult words.

Take the quiz

True or False?

Test your knowledge - and maybe learn something along the way.

Take the quiz

Word Winder's CrossWinder

Word Winder's CrossWinder

A game of winding words.

Play the game