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sigmoid

play
adjective sig·moid \ˈsig-ˌmȯid\

Definition of sigmoid

  1. 1a :  curved like the letter Cb :  curved in two directions like the letter S

  2. 2 :  of, relating to, or being the sigmoid colon

sigmoidally play \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).

Variants of sigmoid

also sigmoidal play \sig-ˈmȯi-dəl\

Origin of sigmoid

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


First Known Use: 1670


Learn More about sigmoid

  1. Medical Dictionary: Definition of "sigmoid"


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