(Photometric) Standard Lamp
A lamp which has been calibrated to give a known value of luminous flux, colour temperature, or luminous intensity in a specified direction, under specified conditions of operation. Such lamps are used as standards in photometric measurements.
Note: Standard lamps include both Secondary Standards and Working Standards as well as the Primary Standard. For definitions of these, see Reference: C.I.E.
Please note that this is the term as it stands in the original IALA Dictionary edition (1970-1989)