Plurals of nouns ending in -io

Dusting Off Nouns Ending in "-io"

As we inventory the curious objects in an Italian antique shop, you will notice many masculine items end in -io, such as calamaio (inkwell) and leggio (reading stand).

When making these nouns plural, they will end in either a single -i or a double -ii. The trick lies in knowing where the stress falls in the singular word.

Plurals with an Unstressed "i"

For the vast majority of nouns ending in -io, the stress falls on a syllable before the final i (e.g., ca-la-MA-io).

When pluralizing these words, simply drop the final -o. The plural form ends in a single -i.

I clean the silver inkwells.
Pulisco i calamai d'argento.
The reliquaries are on the table.
I reliquiari sono sul tavolo.
There are many inkwells and reliquaries to clean.
Ci sono molti calamai e reliquiari da pulire.

Plurals with a Stressed "i"

If the stress falls directly on the i in the -io ending (e.g., ci-go-LÌ-o), you must keep that stressed i and add the standard plural -i. This results in a double -ii ending.

Listen for this slightly drawn-out ee-ee sound in words like cigolio (creak), leggio (reading stand), and oblio (oblivion).

I hear the creaks of the old skylights.
Sento i cigolii dei vecchi lucernari.
We sell reading stands and old orreries.
Vendiamo leggii e vecchi planetari.
Long oblivions ruin the objects.
I lunghi oblii rovinano gli oggetti.

Masculine Nouns Ending in "-ma"

While sorting through the shop's oddities, you might also find a diadema (diadem or tiara).

Though it ends in -a, diadema is a masculine noun. Words of Greek origin ending in -ma are usually masculine. In the plural, they follow the standard masculine rule, changing the final -a to an -i (diademi).

The diadems are expensive, I know it well.
I diademi sono cari, lo so bene.
I hear the tinklings of the gold diadems.
Sento i tintinnii dei diademi d'oro.