-cosa-

infix

Combines with the prefixes for 1–9 to form complex prefixes referring to 21–29.

OriginEnglish icosa- ← Ancient Greek εἴκοσι (eíkosi) ← Proto-Hellenic *ewī́kəti →
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Meanings

infix

alternative -cos-

  1. IUPACCombines with the prefixes for 1–9 to form complex prefixes referring to 21–29.

Origin

  1. Proto-Indo-European*dwóh₁
  2. Proto-Indo-European*dwi-
  3. Proto-Indo-European*déḱm̥
  4. Proto-Indo-European*(h₁)wídḱm̥ti
  5. Proto-Hellenic*ewī́kəti
  6. Ancient Greekεἴκοσι (eíkosi)
  7. Englishicosa-
  8. English-cosa-

From icosa-, itself from words like icosagon and icosahedron, which ultimately derive from Ancient Greek εἴκοσι (eíkosi).

More words from Ancient Greek

Full word history & related roots →
Cite this entry
APA

-cosa-. (n.d.). In WatkinsX Dictionary. Retrieved November 3, 2026, from https://dictionary.watkinsx.com/word/-cosa-

MLA

“-cosa-.” WatkinsX Dictionary, https://dictionary.watkinsx.com/word/-cosa-. Accessed November 3, 2026.

Chicago

WatkinsX Dictionary, s.v. “-cosa-,” accessed November 3, 2026, https://dictionary.watkinsx.com/word/-cosa-.

Source: -cosa- on Wiktionary, CC BY-SA 4.0.