| Noun | 1. | FM - modulation of the frequency of the (radio) carrier wavemodulation - (electronics) the transmission of a signal by using it to vary a carrier wave; changing the carrier's amplitude or frequency or phase |
| 2. | Fm - a radioactive transuranic metallic element produced by bombarding plutonium with neutronsmetal, metallic element - any of several chemical elements that are usually shiny solids that conduct heat or electricity and can be formed into sheets etc. |