An electrodeless fluorescent lamp and fixture is disclosed which operates radio frequencies and contains a metallic cylinder 9 to suppress capacitive coupling between an induction coil 7 and a plasma in the envelope 1 of the lamp and simultaneously substantially reduce heat in a reentrant cavity 5. The lamp includes a bulbous envelope 1 having a conventional phosphor layer 3 disposed therein. The bulbous envelope 1 contains a suitable ionizable gaseous fill. Upon ionization of the gaseous fill, the phosphor is stimulated to emit visible radiation upon absorption of ultraviolet radiation. The reentrant cavity 5 of the bulbous envelope 1 contains an inducation coil. The cylinder 9 transfers heat from the plasma to the fixture 11 through a base 13, 13a on the envelope 1.