Yan Yue Dao (偃月刀)

Drawing of a Yan Yue Dao, from 'Chou Hai Tu Bian (《籌海圖編》)'.

Yan Yue Dao (偃月刀, lit. 'Reclining moon glaive'), also known as Chun Qiu Da Dao (春秋大刀, lit. 'Spring and autumn great glaive') or simply Da Dao (大刀, lit. 'Great glaive'), is arguably the most iconic Chinese polearm. Due of its association with legendary Chinese general/war deity Guan Yu (關羽), it is also known as Guan Dao (關刀).

Yan Yue Dao is very similar to Zhan Ma Dao (斬馬刀) and can be used in pretty much the same manner (as both are glaive-like polearms). It has a trailing point blade with a sharpened protrusion on the back of its blade that aids in parrying, and always mounts a three-sided butt spike, which distinguish it from other Chinese glaives.

While some Yan Yue Dao are extremely heavy and considered impractical for the battlefield, lightweight version intended as practical weapon do exist.