Main entry: young, immature
Definition: (used of living things especially persons) in an early period of life or development or growth
Usage: young people
Antonyms: old
Definition: (used especially of persons) having lived for a relatively long time or attained a specific age
Definition: people who are old collectively
Antonyms: tough
Definition: resistant to cutting or chewing
Definition: physically toughened
Antonyms: tough
Definition: not given to gentleness or sentimentality
Definition: above average in size or number or quantity or magnitude or extent
Antonyms: big
Definition: on a grand scale
Antonyms: senior
Definition: older; higher in rank; longer in length of tenure or service
Antonyms: much
Definition: (quantifier used with mass nouns) great in quantity or degree or extent
Antonyms: middle
Definition: between an earlier and a later period of time
Antonyms: late
Definition: being or occurring at an advanced period of time or after a usual or expected time
Definition: at or toward an end or late period or stage of development
Antonyms: middle
Definition: of a stage in the development of a language or literature between earlier and later stages
Antonyms: late
Definition: of a later stage in the development of a language or literature; used especially of dead languages
Antonyms: tardily, late, belatedly
Definition: later than usual or than expected
Antonyms: summery
Definition: belonging to or characteristic of or occurring in summer
Antonyms: autumnal
Definition: of or characteristic of or occurring in autumn
Definition: characteristic of or occurring in winter
Main entry: immature, green, unripe, unripened
Definition: not fully developed or mature; not ripe
Usage: unripe fruit; fried green tomatoes; green wood
Main entry: immature, unfledged
Definition: (of birds) not yet having developed feathers
Usage: a small unfledged sparrow on the window sill
Definition: (of birds) having developed feathers or plumage; often used in combination
Antonyms: feathered
Definition: having or covered with feathers
Main entry: immature
Definition: not yet mature
Antonyms: mature
Definition: having reached full natural growth or development
Main entry: immature
Definition: characteristic of a lack of maturity
Usage: immature behavior
Antonyms: mature
Definition: characteristic of maturity
Definition: a fully developed person from maturity onward