Eleven times in the Book of Mormon a “cimeter” is mentioned as a weapon used in times of war, such as in Mosah 9:16:
And it came to pass that I did arm them with bows, and with arrows, with swords, and with cimeters, and with clubs, and with slings, and with all manner of weapons which we could invent, and I and my people did go forth against the Lamanites to battle.
A cimeter is a curved sword with a cutting edge on one side and was originally thought to be anachronistic but has now been proven to have existed in the New and Old World. In fact cimeters are mentioned multiple times in the Bible but this was only found out with the discovery of the Dead Sea Scrolls.
Joseph Smith would have been familiar with common weapons but where did he learn what a cimeter was? Why would he have included weapons that would be rejected as anachronistic?