Meanings
comparative more sigmoid · superlative most sigmoid
- archaicSemi-circular, like the uncial or lunate sigma (similar to English C).
- Curved in two directions, like the letter "S", or the Greek ς (sigma); having a serpentine shape.
Synonyms: S-shaped
- mathematicsExhibiting logistic growth; having a graph that accelerates until it reaches a carrying capacity.
Synonyms: S-shaped
plural sigmoids
- abbreviationellipsisanatomyEllipsis of sigmoid colon.
- abbreviationellipsismathematicsEllipsis of sigmoid function.
1 more example
If we had the textbook from a hundred years in the future that contains all the simple ideas that actually work, that take so long to identify in practice — the ReLUs instead of sigmoids — for those of us who’ve been following AI for, like, more than the last couple of years and know what I’m taking about there.
2023 June 29th, “AI will kill all of us | Eliezer Yudkowsky interview” (16:12–16:28 from the start), in The David Pakman Show, spoken by Eliezer Yudkowsky, via YouTube
Synonyms & antonyms
adjectiveCurved in two directions, like the letter "S", or the Greek ς (sigma); having a serpentine shape.
adjectiveExhibiting logistic growth; having a graph that accelerates until it reaches a carrying capacity.
adjectiveRelating to the sigmoid colon.
More synonyms by meaning
adjectiveof or relating to the sigmoid flexure in the large intestine
Synonym sets from Open English WordNet, CC BY 4.0.
Origin
- Ancient Greekσῖγμᾰ (sîgmă)
- Proto-Indo-European*weyd-
- Proto-Indo-European*wéydos
- Proto-Hellenic*wéidos
- Ancient Greekεἶδος (eîdos)
- Ancient Greekσῑγμοειδής (sīgmoeidḗs)
- Englishsigmoid
Borrowing from Ancient Greek σῑγμοειδής (sīgmoeidḗs, “of the shape of sigma”), from σῖγμᾰ (sîgmă, “sigma”) + -ο- (-o-) + -ειδής (-eidḗs, “-oid, -like”); Equivalent to sigma + -oid. Compare with French sigmoïde.
More words from Ancient Greek
Full word history & related roots →Translations
Catalan sigmoïdal, sigmoide
- sigmoïdalrelating to the sigmoid colon
- sigmoideS-shaped, sigma-shaped
Chinese Mandarin 乙狀結腸的 /乙状结肠的, 乙狀 /乙状
- 乙狀結腸的 /乙状结肠的 (yǐzhuàngjiécháng de)relating to the sigmoid colon
- 乙狀 /乙状 (yǐzhuàng)S-shaped, sigma-shaped
Esperanto sforma, so-forma
- sformaS-shaped, sigma-shaped
- so-formaS-shaped, sigma-shaped
- sigmojdaS-shaped, sigma-shaped
- sigmoidaS-shaped, sigma-shaped
Indonesian sigmoid
- sigmoidS-shaped, sigma-shaped
Spanish sigmoideo, sigmoideo
- sigmoideorelating to the sigmoid colon
- sigmoideoS-shaped, sigma-shaped
Rhymes & wordplay
Rhymes with sigmoid
All rhymes →Cite this entry
sigmoid. (n.d.). In WatkinsX Dictionary. Retrieved November 2, 2026, from https://dictionary.watkinsx.com/word/sigmoid
“sigmoid.” WatkinsX Dictionary, https://dictionary.watkinsx.com/word/sigmoid. Accessed November 2, 2026.
WatkinsX Dictionary, s.v. “sigmoid,” accessed November 2, 2026, https://dictionary.watkinsx.com/word/sigmoid.
Source: sigmoid on Wiktionary, CC BY-SA 4.0.