desuetude

/ˈdɛswɪˌtud/
noun
  1. The state of no longer being used or practiced; disuse.
    • The tradition of writing letters by hand has largely fallen into desuetude.
    • Many old laws have fallen into desuetude and are never enforced.
    • The ancient language fell into desuetude as fewer people spoke it.
Antonyms
What does "desuetude" mean? | whatsthatwordmean | whatsthatwordmean