The story
From truncated + cuboctahedron, referring to a partial construction (the resultant figure needs further distortion to make the faces regular).
Etymology from Wiktionary, CC BY-SA 4.0.
truncated cuboctahedron
Today it means: An Archimedean solid that is isogonal and has twenty-six regular faces (twelve square, eight hexagonal and six octagonal); a great rhombicuboctahedron. Full definition →