[Jim McDougall]

This is a brilliant and as always, thorough, examination of the scythe and the weapons it inspired through history. Its an amazing and as seen here, complex topic as the etymology and use of the term of course seems to have been used in some variation such as referring to a deeply curved blade. Clearly the chief advantage of the inside curve is that the blade essentially grabs its target holding to it as it cuts.

The interesting and somewhat mysterious Black Sea 'yataghan' (pictured with burgundy scabbard) was in years before compared to the khopesh of ancient Egypt, which of course was a purely visual notion. It was also similar to an Assyrian sword with similar recurve. These 18th century swords were later determined to be Laz Bichagi from Transcaucasian regions and Anatolia.
I would note the Assyrian sword was shown in Burton (1884, p.208) as a 'sapara' and had a blade with inside curve. Other Assyrian weapons were hafted sickle types with deep curve as well.

Other modern versions of 'sickle' sword would be the shotel of Ethiopia of 19th century used into 20th. This deeply parabolic bladed sword was believed to facilitate reaching over or around a defending shield. (last image)

The 16th century German saber from Germany with sickle blade is most interesting and reminds me somewhat of art by Durer with similar dusagge type swords. The chain on the hilt is of interest and I hadnt realized this affectation was this early. It is of course well known on court and various European dress swords of late 17th through 18th c. and later.
The runic inscriptions are amazing!!!

Great note on the grinding wheels and these machines in the great Shotley Bridge mystery! the fascinating book by Keith revealing more on this subject as well as the complex intrigues of sword making in England in the17th into 18th century. Some of the most tenacious research I have ever seen.