sig·​moid | \ ˈsig-ˌmȯid \
variants: or less commonly sigmoidal \ sig-​ˈmȯi-​dᵊl \

Definition of sigmoid 

1a : curved like the letter C
b : curved in two directions like the letter S
2 : of, relating to, or being the sigmoid colon

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Other Words from sigmoid

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).

First Known Use of sigmoid

1670, in the meaning defined at sense 1a

History and Etymology for sigmoid

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

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Time Traveler for sigmoid

The first known use of sigmoid was in 1670

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More Definitions for sigmoid


sig·​moid | \ ˈsig-ˌmȯid \

Medical Definition of sigmoid 

(Entry 1 of 2)

1a : 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



Medical Definition of sigmoid (Entry 2 of 2)

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