Find Antonyms
grownup Antonyms
Opposite of grownup
Because the opposite of grownup shifts with each meaning, the 20 antonyms and opposite words below are separated across 3 exact definitions and ranked by contrast strength.
• noun (Context 1)
A physically mature person; an adult (used especially by or in relation to children).
Usage Example
"The children sat at the small table in the kitchen while the grownups talked in the dining room."
Strongest
child
kid
minor
juvenile
youngster
Strong
youth
baby
infant
toddler
adolescent
• adjective (Context 2)
Fully developed and physically mature; having reached adulthood.
Usage Example
"Their two young children now live in different cities and have careers of their own."
Strongest
young
juvenile
underage
Strong
immature
adolescent
prepubescent
• adjective (Context 3)
Characteristic of, suitable for, or behaving like a sensible, responsible adult rather than a child.
Usage Example
"Negotiating a peaceful compromise was a very childish way to handle the disagreement."
Strongest
childish
immature
juvenile
infantile
babyish
Strong
puerile
adolescent
irresponsible
petty
Similar words to grownup
Words similar to grownup shift depending on context. Common synonyms include:
grown-up
mature
adult
grown
fully-grown
full-grown
of age
responsible
Cite this Entry
Wordmom. (2026). Antonyms for Grownup. In Wordmom Thesaurus. Retrieved Nov 5, 2026, from https://wordmom.com/antonyms/grownup