The general lines of diachronics of Lombard and Piedmontese plural declension are drawn here:

Feminine

In Lombard and Piedmontese, feminine plural is generally derived from Latin first declension accusative -as (compare Romance plurals § Origin of vocalic plurals); nouns from other classes first collapsed there; some concrete realisations are:

• -as > -a
• -as > -es > -e
• -as > -es > -ei > -i
• -as > -es > -ei > -i > -e
• -as > -es > -ei > -i > -∅

Masculine

On the contrary, masculine plural is generally derived from Latin second declension nominative -i; this suffix eventually drops or gives rise to palatalisation or metaphonesis; some concrete realisations are:

• -li > -lj > -gl > -j
• -ni > -nj > -gn
• -ti > -tj > -cc
• Metaphonesis (in regression) : orti > öört;
• Neutralisation: -i > -∅

See also

• Western Lombard
• Eastern Lombard
• Piedmontese
• Romance plurals

References

• G.Hull: the linguistic unity of Northern Italy and Rhaetia, PhD thesis, University of Sydney West (1982)
• E.Banfi, G.Bonfadini, P.Cordin, M.Iliescu: Italia Settentrionale: Crocevia di idiomi Romanzi, Atti del convegno internazionale di studi, Trent 21-23 Ottobre 1993 Niemayer, Tübingen, 1995