Ducat and Green light

Ducat noun - Formerly a gold coin of various European countries.

Green light and ducat are semantically related. in authorization topic. In some cases you can use "Green light" instead a noun "Ducat".

Green light noun - The approval by someone in authority for the doing of something.

Ducat and green light are semantically related. Sometimes you can use "Ducat" instead a noun phrase "Green light".