shashka
The shashka is a kind of sabre; a single-edged, single-handed, and guardless backsword. The comparatively subtle curve of a shashka blade puts the weapon midway between a typically curved sabre and a straight sword. Its pommel generally protrudes to the side, causing a hooked hilt shape.
(Danbooru post #2763050 for example)
It is often wielded by Russian or Ukrainian cossacks.