A Twibill

1. (carpentry) A two-edged tool used in gate-type hurdle-making for cutting out mortises, with a flat chisel and a mortise chisel or hook, similar to the much larger French carpenter's tool, the besaiguë (or bisaiguë).
2. (dialectal, Britain) A mattock with one blade like an axe and the other like an adze.
3. (dialectal, England) A reaping hook, especially for cutting beans and peas.
4. (obsolete) A double-bladed halberd or battle-axe.