Why is the ninth month called September?
1670s, "wedge shaped," from French cunéiforme (16c.), from Latin cuneus "a wedge, wedge-shaped thing," of unknown origin, + French -forme (see form (n.)). Applied to characters in ancient Middle Eastern inscriptions made with wedge-shaped writing tools; first used in this sense by German physician and traveller Engelbert Kämpfer (1681-1716); in English from 1818. As a noun from 1862.
cuneiform (kyōō'nē-ə-fôrm', kyōō-nē'-)
Of, relating to, or being a wedge-shaped bone or cartilage.