Meaning of sigmoid in English:


Pronunciation /ˈsɪɡmɔɪd/


  • 1Curved like the uncial sigma; crescent-shaped.

    ‘To isolate deviations from typical tree growth, we developed a model based on the amount of shoot elongation, which over equal time intervals approximates a sigmoid curve.’
    • ‘The growth curve of the fruit of Marisol clementine fitted a single sigmoid curve well.’
    • ‘Usually, a time course of plant growth follows a sigmoid curve, which can be described by a logistic function.’
    • ‘Fruit development was described by an approximately sigmoid growth pattern based on fresh weight, irrespective of cultivar.’
    • ‘The main body of the element comprises a longitudinal bony buttress that supports a very slight sigmoid row containing a minimum of five shallow tooth sockets.’
  • 2S-shaped.

    ‘First, the cumulative adoption of an innovation over time follows an S-shaped or sigmoid curve.’
    • ‘‘The river flows in long sigmoid Curves,’ he wrote, ‘through an alluvial valley of no great width.’’
    • ‘A series of unsuccessful attempts at scheduling surgery for her sigmoid colectomy followed because of complications with her neutrophil count and hospitalization for new onset atrial fibrillation.’


short for sigmoid colon
‘The sigmoid may lie in the abdomen just inferior to the splenic flexure of the transverse colon, or in the right iliac fossa.’
  • ‘Although sigmoid volvulus can resolve spontaneously, nonoperative management begins with fluid resuscitation and antibiotics, followed by barium enema detorsion of the sigmoid.’
  • ‘The most frequently involved site is the sigmoid.’
  • ‘An enema shows a normal sized rectum and small caliber sigmoid and descending colon with a transition zone in colonic caliber occurring at the level of the splenic flexure.’


Late 17th century from Greek sigmoeidēs, from sigma (see sigma).