Essive case

The essive case carries the meaning of a temporary state of being, often equivalent to the English "as a ...".

In the Finnish language, this case is marked by adding "na" to the genitive stem of the noun, but with strong consonant gradation[?]. Example: "lapsi" -> "child", "lapsena" -> "as a child", "when (I) was a child".

In Finnish, it is also used for specifying days and dates when something happens. For example: "maanantaina" -> "on monday", "kuudentena joulukuuta" -> "on the 6th of December".