The Adze (weapon)
This is essentially the one handed version of the two handed war mattock weapon.
The medieval adze was one of the few weapons with an edge that could both tear open armor plate as well as inflict devastating concussion blows. The adze usually had a beak-like blade opposite a faceted hammer, making it a combination of a mace and pick. The weight of the metal head concentrated on the sharp point of the beak after a full swing easily pierced both chain and plate mail. A spear-like tip on some versions allowed for thrusting as well as swinging. While some war hammers were of all metal construction, most were socketed metal heads attached to wooden hafts; metal reinforcement bars (termed langets or cheeks) along the side of the wood haft prevented the hammer head from breaking off during combat.
The adze was a traditional carpenter's tool with a long thin axe-like blade attached at a right angle to the handle; they were used for cutting grooves. The Maori of New Zealand used adzes (called a Toki) as war weapons. Theirs were carved of bone or jade, usually decorated very elaborately, and lashed to a wooden handle.