What does "swingle" mean?

Additional senses

1. 2.To clean, as flax, by beating it with a swingle, so as to separate the coarse parts and the woody substance from it; to scutch.
2. 3.To beat off the tops of without pulling up the roots; -- said of weeds. [Prov. Eng.] Forby.
3. 4.A wooden instrument like a large knife, about two feet long, with one thin edge, used for beating and cleaning flax; a scutcher; - - called also swingling knife, swingling staff, and swingling wand.