Sigmoid

a.	1.	Curved in two directions, like the letter S, or the Greek
Sigmoid flexure
(Anat.) the last curve of the colon before it terminates in the rectum. See Illust. under Digestive.

Sigmoid valves

(Anat.) See Semilunar valves, under Semilunar.

Adj.	1.	sigmoid - curved in two directions (like the letter S)
	2.	sigmoid - of or relating to the sigmoid flexure in the large intestine Synonyms: sigmoidal

Cynthian, S-shaped, ambagious, anfractuous, bicorn, circuitous, circumlocutory, convolutional, corniform, crescent, crescent-shaped, crescentic, crescentiform, crescentlike, falcate, falciform, flexuose, flexuous, horn-shaped, horned, involute, involuted, involutional, labyrinthine, lunar, lunate, luniform, lunular, mazy, meandering, meandrous, menisciform, meniscoid, moon-shaped, moonlike, rivose, rivulose, roundabout, ruffled, semicircular, semilunar, serpentine, sickle-like, sickle-shaped, sinuate, sinuose, sinuous, snaky, torsional, tortile, tortuous, turning, twisting, twisty, two-horned, whorled, winding, wreathlike, wreathy