halberd, arms, festival car, float, tasselled spear radical (no. 62)
戈 centers on a pole weapon with a blade: a halberd or tasselled spear. The radical sense is the same weapon shape used as a component in other characters, and the festival car/float meaning is a rare extended use related to decorative spears.
戈 is a pictograph of a halberd or dagger-axe, an ancient pole weapon. The modern form retains the basic shape of the blade and shaft.
The shape suggests a long pole with a blade at the top: the horizontal stroke is the blade, the slanted stroke is the shaft, and the dot is the tassel. Picture a halberd with a tassel hanging from it.
For カ, imagine a car (カ) decorated as a festival float with tasselled spears mounted on it: car -> カ, and the float carries the halberd.
ge (ancient Chinese dagger-axe)
swords; arms; warfare
weapon; arms; shield and spear
to open hostilities; to be at war
to open hostilities; to take up arms; to start a war
kanji "spear" radical at right
kanji "spear" radical at right
bronze dagger-axe