Where does “sìobhalta” come from?

sìobhalta (Scottish Gaelic) comes from Middle Irish síbíalta, from Middle English civil, from Old French civil, from Latin cīvīlis, from Latin -ilis, from Proto-Italic -elis, from Proto-Indo-European -elis, from Proto-Indo-European -lós — Forms agent nouns from verbal roots.

sìobhalta (Scottish Gaelic): civil, civilian