Compare each case across both numbers. The forms below are the noun's stored reference paradigm.
Singular and plural case forms for костюм
Case
Singular
Plural
Nominative
костюм
костюмы
Accusative
костюм
костюмы
Genitive
костюма
костюмов
Dative
костюму
костюмам
Instrumental
костюмом
костюмами
Prepositional
костюме
костюмах
Form pattern
How the forms are built
The paradigm above is authoritative. These notes expose a transparent ending change only when the stored declension family supports one.
Genitive · Singularкостюм- + -а → костюма
Keep the stored stem and add -а.
Show all case-build notes
Nominative · Singularкостюм
This is the dictionary form used to identify the noun.Nominative · Pluralкостюм- + -ы → костюмы
Keep the stored stem and add -ы.Accusative · Singularкостюм- + zero ending → костюм
Remove the zero ending; this form has a zero ending.Accusative · Pluralкостюм- + -ы → костюмы
Keep the stored stem and add -ы.Genitive · Singularкостюм- + -а → костюма
Keep the stored stem and add -а.Genitive · Pluralкостюм- + -ов → костюмов
Keep the stored stem and add -ов.Dative · Singularкостюм- + -у → костюму
Keep the stored stem and add -у.Dative · Pluralкостюм- + -ам → костюмам
Keep the stored stem and add -ам.Instrumental · Singularкостюм- + -ом → костюмом
Keep the stored stem and add -ом.Instrumental · Pluralкостюм- + -ами → костюмами
Keep the stored stem and add -ами.Prepositional · Singularкостюм- + -е → костюме
Keep the stored stem and add -е.Prepositional · Pluralкостюм- + -ах → костюмах
Keep the stored stem and add -ах.