in st. peter's time, dacia was still unconquered territory, the sica was a known form tho from illyrica and thrace and the term was used for assasin's daggers and the assassins themselves, ie. the sicarii of palestine who would have used their own local dagger forms which may or may not have resembled a true sica. recurved and sickle form knives were used thru-out the empire. to us pedants, the term is specific to thrace/dacia/illyria, to a roman in the middle east, the dagger made down the road in antioch by abdul the blacksmith was a generic 'sica' - they likely also had more specific names. ie. 'pugio' for the roman army wasp waisted side-arm. if it looks like a duck, walks like a duck, it's a duck. even if it's made in china.
reminds me of the 'falcata' a name made up by us collectors a century or so ago that would not have been recognised by the people who originally used them.
i still like pete's knife. whatever we call it.