abdomen

noun

ab·​do·​men ˈab-də-mən 

-ˌdō-;

əb-ˈdō-mən,

ab- 

plural abdomens

1

a

: the part of the body between the thorax (see thorax sense 1) and the pelvis with the exception of the back

lesions on the chest and abdomen

… they do away with the need for a waistband, which can cut into your abdomen when you're leaning forwards …

—Liz Dodd

called also belly

b

: the cavity of the abdomen that is lined by peritoneum, is bounded above by the diaphragm, anteriorly by a wall of muscle and tissue, and posteriorly by the spinal column, is continuous below with the pelvic cavity, and contains many of the visceral organs and especially those involved in digestion (such as the stomach, liver, pancreas, kidneys, and intestines) : abdominal cavity

Removal of the gallbladder—a pear-shaped sac in the right side of your abdomen—has little adverse effect on digestion.

—The Mayo Clinic Health Letter

2

: the posterior section of the body behind the thorax (see thorax sense 2) in an arthropod

On a nearby table was a … dish of ants that looked familiar except that they had been feeding on peach nectar and the abdomen of each was a large, swollen, translucent sac.

—The New Yorker

see insect illustration

Synonyms

• belly
• breadbasket [slang]
• gut
• solar plexus
• stomach
• tummy

Examples of abdomen in a Sentence

showed us a tiny tattoo on her abdomen, right next to her belly button

Recent Examples on the Web

Female Joro spiders, known for their yellow and gray abdomens, will lay egg sacs holding 400 to 500 eggs. —Aliza Chasan, CBS News, 18 Sep. 2024

The Doritos effect: Snack ingredient yields invisible mouse After testing the dye on mice tissue samples and raw chicken breast, the researchers rubbed the dye and water solution onto the skulls and abdomens of the mice. —Mike Snider, USA TODAY, 6 Sep. 2024

The veterinarian said Sky needed surgery to have her uterus removed and was suffering from an abdomen infection, which was described as a life-threatening condition, according to the warrant affidavit. —Justin Muszynski, Hartford Courant, 8 Feb. 2024

To stress the spiders, Davis’s co-author, then undergraduate student Christina Vu, restrained them with a forest of pins, threading them between the spiders’ legs and over their abdomens so that the spiders could wiggle around but not move from the spot. —Stephanie Pappas, Scientific American, 12 Aug. 2024

Word History

Etymology

borrowed from Middle French & Latin; Middle French, borrowed from Latin abdōmen "fat underpart of an animal, belly, paunch," of uncertain origin

Note: Often seen as a derivative of abdere, "to hide, conceal," i.e., "that which is hidden," based on a nominal ablaut form *dhoh₁- from the root *dheh₁- "put." However, Latin abdōmen refers primarily to a body part of animals, and more or less humorously of humans; such usage suggests something prominent rather than something concealed, so the derivation looks somewhat unlikely.

First Known Use

circa 1541, in the meaning defined at sense 1a

Kids Definition

abdomen

noun

ab·​do·​men ˈab-də-mən 

ab-ˈdō-mən

1

a

: the part of the body between the chest and the hips

b

: the body cavity containing the chief digestive organs

called also abdominal cavity

2

: the hind portion of the body behind the thorax in an arthropod see insect illustration

abdominal

ab-ˈdäm-ən-ᵊl 

-nᵊl

adjective

abdominally

-ē 

adverb

Medical Definition

abdomen

noun

ab·​do·​men ˈab-də-mən, -ˌdō-; əb-ˈdō-mən, ab- 

plural abdomens also abdomina ab-ˈdäm-ən-ə 

1

a

: the part of the body between the thorax and the pelvis with the exception of the back

called also belly

b

: the cavity of the abdomen that is lined by the peritoneum, is bounded above by the diaphragm, anteriorly by a wall of muscle and tissue, and posteriorly by the spinal column, is continuous below with the pelvic cavity, and contains many of the visceral organs and especially those involved in digestion (such as the stomach, liver, pancreas, kidneys, and intestines) : abdominal cavity

2

: the posterior often elongated region of the body behind the thorax in arthropods