Partitive case

The partitive case (abbreviated PTV or more ambiguously PART) is a grammatical case which denotes "partialness", "without result", or "without specific identity". It is also used in contexts where a subgroup is selected from a larger group, or with numbers.

In the Finnic languages, such as Finnish and Estonian, this case is often used to express unknown identities and irresultative actions. For example, it is found in the following circumstances, with the characteristic ending of -a or -ta:

Where not mentioned, the accusative case would be ungrammatical. For example, the partitive must always be used after singular numerals.

As an example of the irresultative meaning of the partitive, ammuin karhun (accusative) means "I shot the bear (dead)", whereas ammuin karhua (partitive) means "I shot (at) the bear" without specifying if it was even hit. Notice that Finnish has no native future tense, so that the partitive provides an important reference to the present as opposed to the future. Thus luen kirjaa means "I am reading a/the book" whereas luen kirjan means I will read a/the book". Thus "luen" can mean "I am reading" or "I will read" depending on the case form of the word that follows. The partitive form kirjaa indicates incompleted action and hence the meaning of the verb form is present tense. The accusative form kirjan indicates completed action when used with the past tense verb but indicates planned future action when used with a verb in the present tense. Hence luen kirjan means "I will read the book".

The case with an unspecified identity is onko teillä kirjoja, which uses the partitive, because it refers to unspecified books, as contrasted to nominative onko teillä (ne) kirjat?, which means "do you have (those) books?"

The partitive case comes from the older ablative case. This meaning is preserved e.g. in kotoa (from home), takaa (from behind), where it means "from".

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