Twibil \Twi"bil\, n. [AS. twibill; twi- (in comp.) two + bill, bil, an ax, hoe, bill. See {Twice}, and {Bill} a cutting instrument.] 1. A kind of mattock, or ax; esp., a tool like a pickax, but having, instead of the points, flat terminations, one of which is parallel to the handle, the other perpendicular to it. [Prov. Eng.] [1913 Webster] 2. A tool for making mortises. [Obs.] [1913 Webster] 3. A reaping hook. [1913 Webster]