AIDS

noun
\ ˈādz How to pronounce AIDS (audio) \

Definition of AIDS

: a disease of the human immune system that is characterized cytologically especially by reduction in the numbers of CD4-bearing helper T cells to 20 percent or less of normal thereby rendering the subject highly vulnerable to life-threatening conditions (such as Pneumocystis carinii pneumonia) and to some (such as Kaposi's sarcoma) that become life-threatening and that is caused by infection with HIV commonly transmitted in infected blood especially during illicit intravenous drug use and in bodily secretions (such as semen) during sexual intercourse

First Known Use of AIDS

1982, in the meaning defined above

History and Etymology for AIDS

acquired immunodeficiency syndrome

Keep scrolling for more

Learn More About AIDS

Statistics for AIDS

Cite this Entry

“AIDS.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/AIDS. Accessed 24 Jul. 2021.

Style: MLA
MLACheck Mark Icon ChicagoCheck Mark Icon APACheck Mark Icon Merriam-WebsterCheck Mark Icon

Keep scrolling for more

More Definitions for AIDS

AIDS

noun

English Language Learners Definition of AIDS

: a serious disease of the immune system that is caused by infection with a virus

AIDS

noun
\ ˈādz How to pronounce AIDS (audio) \

Kids Definition of AIDS

: a serious disease of the human immune system in which large numbers of the cells that help the body fight infection are destroyed by the HIV virus carried in the blood and other fluids of the body

AIDS

noun
\ ˈādz How to pronounce AIDS (audio) \

Medical Definition of AIDS

: a disease of the human immune system that is characterized cytologically especially by a reduction in the numbers of CD4-bearing helper T cells to 20 percent or less of normal thereby rendering the subject highly vulnerable to life-threatening conditions (as Pneumocystis carinii pneumonia) and to some that become life threatening (as Kaposi's sarcoma) and that is caused by infection with HIV commonly transmitted in infected blood especially during illicit intravenous drug use and in bodily secretions (as semen) during sexual intercourse

called also acquired immune deficiency syndrome, acquired immunodeficiency syndrome

More from Merriam-Webster on AIDS

Thesaurus: All synonyms and antonyms for AIDS

Nglish: Translation of AIDS for Spanish Speakers

Britannica English: Translation of AIDS for Arabic Speakers

WORD OF THE DAY

Test Your Vocabulary

Dog Words Quiz

  • shiba puppy more or less demanding cuddles
  • Which of the following animals has a dog in its etymology?
True or False

Test your knowledge - and maybe learn something along the way.

TAKE THE QUIZ
Universal Daily Crossword

A daily challenge for crossword fanatics.

TAKE THE QUIZ
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!