hexads

Their bombs and torpedoes ripped and tore into the structure beneath the invulnerable shield and exploded, demolishing and hurling aside like straws, the walls, projectors, hexads and vast mountains of earth.

Spacehounds of IPC 1927

On the meta level the ten-atomed bodies are set free, and the twelve-atomed divide into duads and decads, thus yielding seventy-two decads and thirty-six duads; the duads, however, at once recombine into hexads, thus giving only twelve meta elements, or eighty-four in all from the funnels.

Occult Chemistry Clairvoyant Observations on the Chemical Elements Annie Wood Besant 1890

The instrument is arranged in twelve hexads, each containing four to six identities of a tonality.

NewMusicBox 2010