Falcata, saunion and falarica...

[Thersites]

I would say falcata is a substantive noun in modern Spanish, used to designate n ancient type of sword whose name in Iberian we do not know, and that was described by Romans as a machaera hispana. In ancient Latin falcatus -a -um it was not a noun, but an adjective taken from falx (scythe), seldom used to qualify swords.
Cheers