A billhook is a tool that looks like a big knife with a curved blade and a hook on the end. It is used to cut and trim things like branches, bushes, and hedges.
The hook on the end allows you to pull branches and wood towards you while cutting them. This can be very helpful because it keeps the wood from flying away when you cut it.
Billhooks have been used for a long time and they are still used today by gardeners and farmers who need a tool to help them keep their plants and trees healthy and tidy.