Hexagon
Hexagonal landscape inside V'ger.
A hexagon was a six-sided geometric shape.
In Spock's analysis of the Insectoid starship discovered in 2269, he noted how "[t]he hexagonal shape of the windows suggests a similarity to natural insect designs of Earth, the honeycombs of bees. The individual cells are shaped precisely like this." (TAS: "Beyond the Farthest Star")
In 2376, Icheb created a twenty six-sided polyhedron out of clay, composed of hexagons, octagons, and squares. Seven of Nine was impressed by Icheb's work. (VOY: "Ashes to Ashes")