Arma was an Anatolian Moon god, worshipped by the Hittites and Luwians in the Bronze Age and early Iron Age.
The name derives from the Proto-Anatolian *ʿOrmo- ("wanderer"). He is attested as the Moon god in Hittite and Luwian religion, with the name Arma-. In Lycian he was called Erm̃ma-, Arm̃ma-, in Carian Armo (dative case), and in Lydian Arm-. In cuneiform texts, the name is written with the Sumerograms dEN.ZU or dXXX, in Hieroglyphic Luwian with a crescent Moon symbol, which is transliterated as (DEUS) LUNA.
While the Hattian moon god, Kašku was not worshipped, Hittite and Luwian religion involved extensive worship of Arma. For the Luwians in particular, the moon was associated with the months of pregnancy and Arma was therefore believed to protect pregnant women and to help women giving birth (note Hittite armaḫḫ- ("to impregnate") and armai- ("to be pregnant"). Thus the Moon god had an important role in family religion. He also served as an important guarantor of oaths in state treaties. His wife was Nikkal (the Mesopotamian goddess Ningal).
The most well-known myth in which the Moon god is involved is of Hattian origin. In this story, the Moon god Kašku falls from heaven and lands in the marketplace or gatehouse of the city of Laḫzan . The angry weather god dropped a heavy downpour of rain on the Moon god, who became very afraid. The goddesses Ḫapantali and Kamrušepa eventually saved him using magic spells.