Halberd
A military weapon, especially in use during the 15th and 16th centuries. A kind of combination of spear and battle-axe, consisting of a sharp-edged blade ending in a point, and a spear-head, mounted on a handle five to seven feet long.
By transference, a soldier armed with a halberd; a halberdier. [Below left]
Halberds are still currently carried by the Papal Swiss Guard.

Compare with …

Pike
A weapon consisting of a wooden shaft, typically 14 to 15 feet long, with a pointed head of iron or steel; formerly the chief weapon of a large part of the infantry; superseded in 18th century by the bayonet.
A soldier armed with a pike is generally a pikeman. [Below right]
Possibly the best way in the UK to see pikes and pikemen is either at a Civil war re-enactment or at London’s Lord Mayor’s Show on the second Saturday in November.

And of course there is then …

Spontoon
A species of half-pike or halberd carried by infantry officers in the 18th century (from about 1740); generally 6 to 7 feet in length.