From Old Church Slavonic рьдьръ (rĭdĭrŭ) (Russian), via vowel assimilation from *ръдьръ (*rŭdĭrŭ), from Proto-Slavic *rъdrъ; cognate with Old East Slavic ръдръ (rŭdrŭ). рьдьръ (rĭdĭrŭ) + -ый (-yj) developed to *ре́дрый (*rédryj), then to the modern form рёдрый (rjódryj) by diphthongization (see History of the Russian language § The yo vowel on Wikipedia).
рёдрый • (rjódryj)
masculine | neuter | feminine | plural | ||
---|---|---|---|---|---|
nominative | рёдрый rjódryj |
рёдрое rjódroje |
рёдрая rjódraja |
рёдрые rjódryje | |
genitive | рёдрого rjódrovo |
рёдрой rjódroj |
рёдрых rjódryx | ||
dative | рёдрому rjódromu |
рёдрой rjódroj |
рёдрым rjódrym | ||
accusative | animate | рёдрого rjódrovo |
рёдрое rjódroje |
рёдрую rjódruju |
рёдрых rjódryx |
inanimate | рёдрый rjódryj |
рёдрые rjódryje | |||
instrumental | рёдрым rjódrym |
рёдрой, рёдрою rjódroj, rjódroju |
рёдрыми rjódrymi | ||
prepositional | рёдром rjódrom |
рёдрой rjódroj |
рёдрых rjódryx |