Origin: from the concept of cases as “declining” from the nominative: cf. case,Gram.
Origin: ME declenson < OFr declinaison < L declinatio, a bending aside, inflection (< pp. of declinare: see decline): ME form infl. by assoc. with L descensio, a descending: see descend
See declension in American Heritage Dictionary 4
Origin: Middle English declenson
Origin: , from Old French declinaison
Origin: , from Latin dēclīnātiō, dēclīnātiōn-, grammatical declension, declination; see declination.
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