Bygone and Demode

Bygone adjective - No longer existing.

Demode and bygone are semantically related In some cases you can use "Demode" instead an adjective "Bygone".

Demode adjective - Out of fashion.

Bygone and demode are semantically related in old topic. Sometimes you can use "Bygone" instead an adjective "Demode", if it concerns topics such as old-fashioned, antiquated. obsolete substitute