Demo and Sit-down

Demo noun - A mass meeting for the purpose of displaying or arousing support for a cause or person.

Sit-down and demo are semantically related. In some cases you can use "Sit-down" instead a noun "Demo".

Sit-down noun - A strike in which workers refuse to leave the workplace until a settlement is reached.

Demo and sit-down are semantically related. Sometimes you can use "Demo" instead a noun phrase "Sit-down".