What is the meaning of Billhook?

A medieval polearm, fitted to a long handle, sometimes with an L-shaped tine or a spike protruding from the side or the end of the blade for tackling the opponent; a bill.

An agricultural hand tool often with a curved or hooked end to the blade used for pruning or cutting thick, woody plants.

A part of the knotting mechanism in a reaper-binder or baler (agricultural machinery).

Rare spelling of bill hook (spiked hook used in shops for hanging papers).

Rare spelling of bill hook (sharply pointed spike on honeyguide hatchlings' mandibles).

To use a billhook

Source: wiktionary.org