Where does “fascio” come from?

fascio (Latin) comes from Latin fascia, from Proto-Indo-European bʰasḱ- — bundle, heap, load.

Ancestry of “fascio”, step by step

Step	Language	Word	Meaning
1	Latin	fascia	band, bandage, swathe, strip, ribbon; necktie
2	Proto-Indo-European	bʰasḱ-	bundle, heap, load

fascio — Etymology, Origin & Word History | Etymology Explorer