adult

[uh-duhlt, ad-uhlt]

noun

1. a person who is fully grown or developed or of age.

2. a full-grown animal or plant.

3. a person who has attained the age of maturity as specified by law.

adjective

1. having attained full size and strength; grown up; mature.

   an adult person, animal, or plant.

2. of, relating to, or befitting adults.

3. intended for adults; not suitable for children.

   adult entertainment.

verb (used without object)

1. Informal.,  (of a young person) to do things and assume responsibilities that are associated with being an adult; act like an adult (usually used facetiously about minor accomplishments).

   I cook dinner for myself most nights—guess that means I'm adulting.

adult

/ ˈædʌlt, əˈdʌlt /

adjective

1. having reached maturity; fully developed

2. of or intended for mature people

   adult education

3. regarded as suitable only for adults, because of being pornographic

   adult films and magazines

noun

1. a person who has attained maturity; a grownup

2. a mature fully grown animal or plant

3. law a person who has attained the age of legal majority (18 years for most purposes) Compare infant

Other Word Forms

• adulthood noun
• adultlike adjective
• adultly adverb
• adultness noun
• nonadult adjective
• quasi-adult adjective
• subadult adjective
• subadultness noun
• unadult adjective

Word History and Origins

Origin of adult¹

First recorded in 1525–35; from Latin adultus “grown” (past participle of adolēre “to make grow”), equivalent to ad- ad- + ul- (identical with base al- in aliment ( def. ) ) + -tus past participle suffix

Word History and Origins

Origin of adult¹

C16: from Latin adultus, from adolēscere to grow up, from alēscere to grow, from alēre to feed, nourish

Example Sentences

But, then again, neither is motherhood; neither is being an adult; neither is getting out of bed every day and seeing what new horrors might await once we leave the house.

Read more on Salon

Parents at several schools were sent warnings after it was found a URL printed in the Spy Dog, Spy Cat and Spy Pups books by Derby author Andrew Cope was linking to "inappropriate" adult content.

Read more on BBC

The reality is that many Americans, including the vast majority of young adults, cannot even define what a deductible is, according to a survey by the National Association of Insurance Commissioners.

Read more on MarketWatch

The everyday costs faced in retirement have outpaced inflation, putting a financial strain on older adults.

Read more on MarketWatch

When kids see adults scrolling their phones at all hours of the day, they begin to think this is normal and acceptable behavior.

Read more on Wall Street Journal

Related Words

• man 
• person 
• woman 

When To Use

What does adult mean?

An adult is a person who is fully grown or developed. This could refer to a person’s body being done growing or their mind being fully developed. An adult child is someone’s child who is fully grown, as in Murray’s adult children are all married and have children of their own.An adult is also a person who has reached an age that their society says allows them responsibilities and benefits not allowed to children. For example, in the United States someone who is 18 years old is in many cases considered an adult. Eighteen-year-olds can vote, sign a contract, join the military, and other actions children are not allowed to do.An adult can also be a fully grown or matured plant or animal, as in Once my puppy becomes an adult, I’ll need to get them a bigger crate.Adult can also be used to describe something related to adults or adulthood, such as adult responsibilities—like paying rent.Adult can also be used to describe something not suitable for children. Things labeled as adult entertainment, for example, often include explicit sexual content.Informally, adult can be used as a verb meaning to take on responsibilities usually reserved for adults, such as owning a house. It’s often used humorously to describe small responsibilities, as in Tanya really adulted today by putting away her laundry.