the masthead, the logo and common elements displayed at the top of each page of a website.

radio masts and towers, typically, tall structures designed to support antennas (also known as aerials in the UK) for telecommunications and broadcasting, including television

masthead (rigging), a method of rigging a sailing vessel, where the forestay runs from the top of the mast to the bow or bowsprit. As opposed to a fractional rig where the forestay starts from a point below the masthead.

mast (sailing), a tall vertical pole of a sailing ship which supports the sails

the masthead (publishing), a list, usually found on the editorial page of a newspaper or other periodical, listing the publisher, editorial board, advertising rates, etc.