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Synonyms

adult

American  
[uh-duhlt, ad-uhlt] / əˈdʌlt, ˈæd ʌlt /

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 British  
/ 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

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

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

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Usage

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.

Other Word Forms

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

Etymology

Origin of adult

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

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

If I ever actually did this Glitch for real, I’d be an adult with years of time traveling under my belt.

From Literature

“Nature is so powerful,” he said, sitting on a couch in the new house, which he built for his adult twin daughters.

From Los Angeles Times

The company submitted an application to the FDA in January for use of the tests in adults with an elevated risk of cancer.

From The Wall Street Journal

She said the behaviour appeared to be limited to certain individuals rather than widespread across the population, with every recorded case involving an adult male seal.

From BBC

Annabelle Chang opened the first young adult bookstore in the country when she was 16.

From Los Angeles Times