spear or pilum?

[M. Demetrius]

Don't forget also, that many cultures used iron tipped javelins that partly or very closely resembled the pilum in function...solifera in Spain, angon and gaesum in other Celtic and Germanic cultures, and add in that there were at least three generic types of pila, and the whole questions gets a little harder to pin down. Some pila had small leaf shaped points, others the more often seen pyramid.

So is it safe to say that when it comes right down to the razor, nobody totally knows for sure?