Superlative adjectives describe the absolute highest or lowest degree of a quality. In their basic form, they usually end in -in (e.g., korkein for "highest", kuumin for "hottest"). When inflecting them into other grammatical cases to talk about geographical extremes or breaking records, the stem changes to either a strong (-impa- / -impä-) or weak (-imma- / -immä-) form.
The Strong Stem: -impa- / -impä-
If the case ending leaves the syllable open, or in the illative case (-an / -än), the stem stays strong as -impa- / -impä-.
| Basic Form | Strong Stem | Inflected Form |
|---|---|---|
| korkein | korkeimpa- | korkeimpaan (Illative) |
| haastavin | haastavimpa- | haastavimpaan (Illative) |
| kaunein | kauneimpa- | kauneimpaan (Illative) |
| We are climbing to the globe's highest mountain range. | Me kiipeämme maapallon korkeimpaan vuoristoon. |
| You should travel to the world's most challenging desert. | Sinun kannattaa matkustaa maailman haastavimpaan autiomaahan. |
The Weak Stem: -imma- / -immä-
If the case ending closes the syllable (which happens with most cases, like the adessive -lla / -llä, inessive -ssa / -ssä, and elative -sta / -stä), the stem weakens to -imma- / -immä-.
| Basic Form | Weak Stem | Inflected Form |
|---|---|---|
| kylmin | kylmimmä- | kylmimmällä (Adessive) |
| kuumin | kuumimma- | kuumimmassa (Inessive) |
| korkein | korkeimma- | korkeimmasta (Elative) |
| The temperature on the coldest glacier is fifty degrees below zero. | Lämpötila kylmimmällä jäätiköllä on viisikymmentä astetta pakkasta. |
| Only the strongest animal survives in the hottest desert. | Kuumimmassa autiomaassa selviytyy vain vahvin eläin. |
| The globe's longest river begins from the highest mountain range. | Maapallon pisin joki alkaa korkeimmasta vuoristosta. |
Plural Cases: -immi- / -impi-
When superlative adjectives are inflected in plural cases, the plural marker -i- replaces the final -a- or -ä- of the stem. The weak stem -imma- becomes -immi-, and the strong stem -impa- becomes -impi-.
| Basic Form | Plural Weak Stem | Inflected Form |
|---|---|---|
| vaikein | vaikeimmi- | vaikeimmissa (Inessive) |
| haastavin | haastavimmi- | haastavimmissa (Inessive) |
| They measured this record in the most difficult conditions of Antarctica. | He mittasivat tämän ennätyksen Etelämantereen vaikeimmissa olosuhteissa. |
| In Antarctica, we live in the most challenging conditions. | Etelämantereella me elämme haastavimmissa olosuhteissa. |