sigmoid

adjective

sig·​moid ˈsig-ˌmȯid 

variants or less commonly sigmoidal

sig-ˈmȯi-dᵊl 

1

a

: curved like the letter C

b

: curved in two directions like the letter S

2

: of, relating to, or being the sigmoid colon

sigmoidally

sig-ˈmȯi-dᵊl-ē 

adverb

Did you know?

The shape sense of sigmoid is most often used in scientific contexts to describe an s-shaped curve on a graph. Usually, though, sigmoid is used in contexts relating to the sigmoid colon-the contracted and crooked part of the colon immediately above the rectum. Sigmoid comes from sigma, the name of the 18th letter of the Greek alphabet. At one time sigma had a common form that was shaped like the Roman letter C (hence sense 1a), but sigma is equivalent to the English letter S (hence sense 1b).

Examples of sigmoid in a Sentence

Recent Examples on the Web

The procedure was necessary to address a diverticular stenosis, or abnormal narrowing, of the sigmoid portion of the colon, said Matteo Bruni, a Holy See spokesman. —Harold Maass, The Week, 5 July 2021

Francis had developed a diverticular stenosis, or narrowing, of the sigmoid portion of the large intestine. —BostonGlobe.com, 6 July 2021

Word History

Etymology

Greek sigmoeidēs, from sigma; from a common form of sigma shaped like the Roman letter C

First Known Use

1670, in the meaning defined at sense 1a

Phrases Containing sigmoid

• sigmoid colon

Podcast

Get Word of the Day delivered to your inbox!

Medical Definition

sigmoid

1 of 2 adjective

sig·​moid ˈsig-ˌmȯid 

1

a

: curved like the letter C

b

: curved in two directions like the letter S

2

: of, relating to, or being the sigmoid colon of the intestine

sigmoid lesions

sigmoid

2 of 2 noun

: sigmoid colon