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

If an adult says they have no underlying health conditions, but do have a prescription from a healthcare provider for “off-label” use of the vaccine, they can get the shot, Thibault confirmed.

From Los Angeles Times

The best I can describe the movie is that it’s an adult coming of age rom-com of male friendship.

From Los Angeles Times

On day four, the boys –- along with five adults -–were heading up from their campsite near Long Lake when they came upon Montgomery.

From Los Angeles Times

Andy looks like a human adult but behaves like an awkward, stammering middle-schooler eager to ingratiate himself with his peers by telling toothless jokes straight out of a Scholastic pun manual.

From Salon

The young adult rom-com follows Avery Blackwell, a rising college freshman who postpones her plans to attend Columbia after a note from her late mother sends her on a scavenger hunt in England.

From Los Angeles Times

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.