This is an irregular feature - both in frequency and oddness - dedicated to a word I came across that I have never previously used.
yataghan (YAHT-eh-gahn) n. A sword of Turkish origin with a double-curved, single-edged blade and an eared pommel, but which lacks a handle guard. Also spelled yatagan.
Yataghans were typically used by janissaries and other infantry soldiers, and these swords were smaller and lighter than ordinary swords and scimitars. The yataghan is named after the town of Yatağan in southwest Turkey, although yatagans were also manufactured in most of the major cities in the Ottoman Empire.
The yataghan differs from the scimitar by virtue of the second blade curve, as scimitars have but one.