des·ue·tude [des-wi-tood, -tyood]
the state of being no longer used or practiced.
Origin: 1425–75; late Middle English < Latin dēsuētūdo, equivalent to dēsuē-, base of dēsuēscere to become disaccustomed to, unlearn ( dē- de- + suēscere to become accustomed to) + -tūdō -tude
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