part of an electric lamp which provides connection to the power supply by means of a lampholder or lamp connector and, in most cases, also serves to retain the electric lamp in the lampholder
Note 1 to entry: In some cases a cap serves as a thermal connection to the luminaire (or its heatsink).
Note 2 to entry: A cap can be an integral part of an electric lamp.
Note 3 to entry: This entry was numbered 845-08-15 in IEC 60050-845:1987.
Note 4 to entry: This entry was numbered 17-119 and 17-76 in CIE S 017:2011.