Di for Quantity vs Partitive Article

Italian has two ways of attaching di to a noun phrase that look almost identical on the surface but do completely different grammatical work. The partitive article — del, dello, dell', della, dei, degli, delle — fuses di with the definite article and means "some" or "any" — an unspecified, indefinite quantity. The preposition di in quantity expressions — un chilo di pane, una tazza di caffè — uses the bare di (no article) to link a quantifying noun to its content. Both involve di, both attach to a noun, both translate as English "of" or "some" — and yet getting them confused is one of the most common errors at B1.

This page disambiguates the two constructions, lays out the contexts where each is required, and walks through the gray zone where speakers genuinely choose between them. By the end, you will know exactly when to say del pane (partitive: some bread), when to say un chilo di pane (preposition: a kilo of bread), and when un chilo del pane is in fact correct after all.

1. The two structures, side by side

This is the structural divide. Same preposition di, two different relationships to the article.

2. The partitive article: vague indefinite quantity

The partitive is treated in detail at Partitive Articles: del, della, dei, delle; here we summarize what you need to disambiguate it from the quantity preposition.

Form

The partitive is di + definite article, fused into one written word:

Function

It means "some" or "any" — an unspecified, indefinite quantity. With uncountable singulars it means "some [substance]"; with countable plurals it works as the plural indefinite article that Italian otherwise lacks.

Diagnostic

If you can replace the partitive with English "some" or "any" and the meaning stays intact, you have a partitive article.

• Vorrei del pane → I'd like some bread → partitive.
• Ci sono delle mele → There are some apples → partitive.

3. The preposition di + bare noun: specific measured quantity

When you specify a quantity with a measure word — a kilo, a liter, a glass, a slice, a piece, a bottle — Italian uses the preposition di without any article between the measure and the substance.

Common measure words

Examples

Why no article

The logic: when you specify a measure, you've already individuated the quantity. Un chilo is one specific kilo; the substance it contains is generic, type-level — "the kind of thing called bread." A definite article would imply you mean the bread (some specific bread you both already have in mind), which is not what you want when ordering at a market.

4. Quantifying adjectives: bare noun, no preposition

A third pattern, easy to confuse with the previous two: when the quantifier is an adjective (molto, poco, tanto, abbastanza, alcuni, qualche), it directly modifies the noun with no preposition at all.

The trap: English speakers, mapping from "a lot of, much of", often insert di: ❌ molto di pane. This is wrong. Only noun-based measures (chilo, bicchiere, sacco) take di; adjectival quantifiers (molto, poco, tanto) attach directly. The exception is un po' di — which acts as a noun phrase ("a bit of") and thus takes di — and un sacco di ("a bag of, a lot of"), which is a noun-based idiom.

5. The three patterns side by side

All three sentences talk about wine. All three express a kind of quantity. They use three different structures because they answer three different questions: Are you drinking? (partitive), How much specifically? (measure word), In what amount typically? (quantifying adjective).

6. The gray zone: when both work

There are real cases where both the partitive and the bare di + noun are grammatical, and the difference is one of register or framing.

Both sentences are good Italian; both are heard at restaurant tables. The first specifies you want exactly a glass; the second leaves the measure to the waiter and just expresses "I want water." Italian speakers choose between them based on whether the measure matters or not.

The gray zone shrinks when the measure is more concrete:

• "Mi dia un chilo del pane" — odd, would prompt the question "del quale?" (which one?) — sounds like the speaker is referring to a specific known bread.
• "Mi dia un chilo di pane" — natural; you want a kilo of bread (any bread).

7. The exception: di + article when the noun is specific

Here is the subtlety that turns the simple rule on its head. The pattern measure word + di + bare noun holds only when the noun is generic, type-level. If the noun is specific — referring to a particular instance you both have in mind — Italian uses di + definite article (a contraction like del, della, dei, degli).

The rule, refined:

• Measure word + di + bare noun: when the noun is generic (any instance of the type).
• Measure word + di + article + noun: when the noun is specific (a particular known instance).

Both are correct in their respective contexts. The difference is type-level vs token-level reference.

8. Other contexts where bare di + noun appears

The "preposition di + bare noun" pattern shows up in several contexts beyond pure quantity. Recognizing them helps reinforce the contrast with the partitive article.

Material

Origin (with essere)

Topic

Comparison

In all these cases, the noun is being treated type-generically, not as a specific known referent. That's why no article appears.

9. The article-restoring trigger

A useful diagnostic: if you can naturally extend the noun with a modifier that makes it specific ("the X you bought, the X over there, the X I mean"), you trigger the article.

This is not unique to quantity. It's the same logic that distinguishes "libro di Marco" (Marco's book — generic possession) from "il libro di Marco che ho letto" (Marco's book that I read — specific) — though in possession you actually want the article anyway: il libro di Marco. The pattern in quantity expressions is more constrained: the bare di + noun signals genericity unambiguously.

10. Italian vs English: what English collapses

English uses "of" and "some" across many of these contexts, leaving Italian to do the disambiguating work:

• English "a kilo of bread" maps to Italian un chilo di pane (no article — generic).
• English "a kilo of the bread" maps to Italian un chilo del pane (with article — specific).
• English "some bread" maps to Italian del pane (partitive — vague portion).

The cleanest mental rule for English speakers: when you would say "of the X" in English (with the definite article), Italian needs the contraction del/della/dei/degli. When you would say "of X" (no article in English), Italian also drops the article: di X alone.

The exception: the partitive article. English "some bread" maps to Italian del pane even though English has no article — because del here is the partitive article, not the contraction di + il. Italian is using the same letters for two different morphological objects, and you have to interpret the structure to know which.

11. Common mistakes

The errors English speakers make most consistently in this area.

12. Quick reference card

The full disambiguation in one table:

The system rewards a single mental check before speaking: Am I expressing a vague portion (partitive), a specific measure (di + bare noun), or a quantifier (adjective + bare noun)? Once that check is automatic, the surface confusion between del and di dissolves — they were never the same construction at all.