narrowcast verb 3noun 1forms 3 verb3 •To transmit a programme to selected individuals or groups, especially via cable. •To send out a message or disseminate information to a specific narrow audience rather than the general public. •To transmit a medical intervention to a specific organ or type of tissue.Cancer therapies can be narrowcasted to the unique genetic signature of a tumor instead of poisoning every dividing cell in the body. — 2018 noun1 •A programme transmitted in this manner. formsnarrowcasted · narrowcasting · narrowcasts