Grammar .

the inflection of nouns, pronouns, and adjectives for categories such as case and number.

the whole set of inflected forms of such a word, or the recital thereof in a fixed order.

a class of such words having similar sets of inflected forms

the Latin second declension.

an act or instance of declining.

a bending, sloping, or moving downward

land with a gentle declension toward the sea.

deterioration; decline.

deviation, as from a standard.

noun

atrophy , decadence , declination , decline , degeneracy , degeneration