Go to 'thermo-' entry Go to 'dino-' entry Go to 'chondro-' entry Go to 'aero-' entry Go to '-logy' entry Go to 'thaumato-' entry Go to 'nano-' entry Go to '-sophy' entry Go to 'bucco-' entry Go to '-ism' entry Go to '-lysis' entry Go to 'galacto-' entry Go to '-anthropy' entry Go to 'pneumo-' entry Go to '-ploitation' entry Go to '-lithic' entry Go to '-sepalous' entry Go to 'onco-' entry Go to '-parous' entry Go to 'dermato-' entry Go to 'multi-' entry Go to 'dodeca-' entry Go to '-zoon' entry Go to 'vermi-' entry Go to 'crystallo-' entry Go to 'biblio-' entry Go to 'eco-' entry Go to 'juxta-' entry Go to 'facio-' entry
Affixes: the building blocks of English
Affixes: the building blocks of English

icos- Also eicos-

Twenty.

[Greek eikosi, twenty.]

An icosahedron is a solid figure with twenty plane faces, especially equilateral triangular ones; an icosidodecahedron (Greek dodeka, twelve) is a solid with 32 faces, 20 equilateral triangles and 12 regular pentagons. Eicosapentaenoic acid, so named because it contains 20 carbon atoms, is a fatty acid found especially in fish oils, a metabolic precursor of prostaglandins; the eicosanoids are a group of hormones and other biologically active substances similarly containing 20 carbon atoms, including leucotrienes, prostaglandins, and thromboxanes.

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