A dozen is a grouping of twelve.
A box of a dozen doughnuts
Half a dozen chargrilled oysters
12 (twelve) is the natural number following 11 and preceding 13. Twelve is a superior highly composite number, divisible by the numbers 2, 3, 4, and 6.
Ancient Hittite relief carving from Yazılıkaya, a sanctuary at Hattusa, depicting twelve gods of the underworld
Image of the globular cluster Messier 12 by Hubble Space Telescope