From Proto-Germanic *ilhilaz, from Proto-Indo-European *h₁elḱ-. The comparative and superlative degrees are taken from the Proto-Germanic adjective *ubilaz (whence English evil), but are themselves from yet another origin, possibly from Proto-Indo-European *wers-.
illr (comparative verri, superlative verst)
This word seems to have a suppletive inflection, using another root in the comparative and superlative forms, than in the positive form.
| singular | masculine | feminine | neuter |
|---|---|---|---|
| nominative | verstr | verst | verst |
| accusative | verstan | versta | verst |
| dative | verstum | verstri | verstu |
| genitive | versts | verstrar | versts |
| plural | masculine | feminine | neuter |
| nominative | verstir | verstar | verst |
| accusative | versta | verstar | verst |
| dative | verstum | verstum | verstum |
| genitive | verstra | verstra | verstra |
| singular | masculine | feminine | neuter |
|---|---|---|---|
| nominative | versti | versta | versta |
| accusative | versta | verstu | versta |
| dative | versta | verstu | versta |
| genitive | versta | verstu | versta |
| plural | masculine | feminine | neuter |
| nominative | verstu | verstu | verstu |
| accusative | verstu | verstu | verstu |
| dative | verstum | verstum | verstum |
| genitive | verstu | verstu | verstu |