Proto-Italic language

The Proto-Italic language is the ancestor of the Italic languages, including notably Latin. It is not directly attested in writing, but has been reconstructed to some degree through the comparative method. Proto-Italic descended from the earlier Proto-Indo-European language.

Proto-Italic had the following diphthongs:

Osthoff's law remained productive in Proto-Italic. This caused long vowels to shorten when they were followed by a sonorant and another consonant in the same syllable: VːRC > VRC. As the long diphthongs were also VːR sequences, they could only occur word-finally, and were shortened elsewhere. Long vowels were also shortened before word-final *-m. This is the cause of the many occurrences of short -a- in, for example, the endings of the ā-stems or of ā-verbs.

Proto-Italic words had a fixed stress on the first syllable of the word. This stress pattern probably remained in most descendants. In Latin, it remained during the Old Latin period, after which it was replaced with the "Classical" penultimate stress pattern.

Nouns could have one of three genders: masculine, feminine and neuter. They declined for seven of the eight Proto-Indo-European cases: nominative, vocative, accusative, genitive, dative, ablative and locative. The instrumental case had been lost. Nouns also declined for number in singular and plural. The dual number was no longer distinguished, although a few remnants (like Latin duo, ambō) still preserved some form of the inherited dual inflection.

This is the "second declension" of Latin. It descends from the Proto-Indo-European thematic declension. Most nouns in this class were masculine or neuter, but there may have been some feminine nouns as well.

This class represents the "first declension" of Latin. It derives primarily from Proto-Indo-European nouns in *-eh₂-, and contained mostly feminine nouns, but maybe a few masculines.

This class contained nouns with stems ending in a variety of consonants. They included root nouns, n-stems, r-stems, s-stems and t-stems among others. They are grouped in Latin under the "third declension", which also includes the i-stems, originally a distinct class.

Masculine and feminine nouns declined alike, while neuters had different forms in the nominative/accusative/vocative.

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