1. grammar set of words that behave similarly: a group of nouns, adjectives, or pronouns that all change their form or word endings in the same way according to gender, number, or grammatical case
2. grammar process of ending words: the process by which some sets of nouns, adjectives, and pronouns vary in form to show gender, number, or grammatical case
3. worsening or falling away: the process of gradually declining or deteriorating
(
formal
)
4. geology downward slope: a downward slope, especially of terrain
[15th century. Via French déclinaison< Latin declination-< declinare "bend away" (see decline), from the idea of inflections deviating from the pure form]
