Where does “assì” come from?

assì (Sicilian) comes from Latin sīc, from Latin sice, from Latin sī, from Proto-Italic sei, from Proto-Indo-European só — this; that.

Ancestry of “assì”, step by step

assì traces back through two separate lines of ancestry.

via Latin sīc

StepLanguageWordMeaning
1Latinsīcyes, indeed (If answering a question)
2Latinsice
3Latinif, supposing that
4Proto-Italicseiso, thus
5Proto-Indo-Europeanthis; that

via Latin ac

StepLanguageWordMeaning
1LatinacAlternative form of atque
Every word from Proto-Indo-European Every word from Proto-Italic seiEvery word from Latin