-lo

From earlier -la-i, from -la +‎ -i.

-lo (front vowel harmony variant -lö)

1. Forms various nouns.

• With bisyllabic stems, the preceding -a-, -ä- usually changes to -e- (compare -ella). e-stems however generally have the -e- turn into an -i-.

-lo

1. (enclitic) Alternative form of lo

   dare (“to give”) → darlo (“to give him”)

   vendere (“to sell”) → venderlo (“to sell him”)

   servire (“to serve”) → servirlo (“to serve him”)

   mangia (“eat!”) → mangialo (“eat him!”)

• Appended to present active infinitive verb forms to derive accusative forms when the object is third singular masculine person. Also appended to second singular person imperative forms. The final -e of the original infinitive is removed :

-are → -arlo

-ere → -erlo

-ire → -irlo

Where the verb ends in -rre, the final re is removed, leaving behind just an -r:

introdurre (“to introduce”) → introdurlo (“to introduce him”)

In any case, after the suffixation, there is only a single r and no vowels immediately before -lo.

-lō

1. dative/ablative masculine/neuter singular of -lus

From Proto-Slavic *-dlo.

-lo (Cyrillic spelling -ло)

1. Suffix appended to words to create a neuter noun, usually denoting senses or objects, used as a pejorative or as an abstract noun.
2. Suffix appended to words to create a masculine or neuter noun, usually for forming diminutives, pejoratives, abstract nouns and for denoting a tool.

• -alo
• -ilo