Three-Ending Adjectives: 1st and 3rd Declension (3-1-3) -ύς -εῖα -ύ

31.8 Adjectives in –ύς –εῖα –ύ

As you study this inflection pattern, note the following:

• Remember that if the stem of the adjective ends in –ε, –ι or –ρ, ᾱ appears instead of η in feminine singular forms. The use of –ᾱ– affects only the GENITIVE and DATIVE SINGULAR for these adjectives, however. The nominative and accusative singular already have short –ᾰ-.
• In the nominative and accusative singular of the masculine and neuter, the stem ends in –υ.
• The masculine accusative singular ending is –ν.
• The masculine nominative and accusative plural are identical: see, e.g., ἡδεῖς.
• Not all of the expected contractions occur: see, e.g., ἡδέος, ἡδέων, and ἡδέα.
• All adjectives of this declension family share the same persistent accent.

(S 297, cf G 158)