Wiktionary
dodecagonal
a. Having twelve sides and twelve angles
Usage examples of "dodecagonal".
The corners of each bar joined its mates on the inside of the barrel, forming a dodecagonal tube about three inches in diameter.
Next you tow your twelve moons into place, positioning them so that they occupy the same synchronous orbit in a stable dodecagonal configuration.
Only the sensory stalks remained the same, feeding the developing brain a dodecagonal impression of the world around it.