| 1. | Electronics. frequency modulation: a method of impressing a signal on a radio carrier wave by varying the frequency of the carrier wave. |
| 2. | Radio. a system of radio broadcasting by means of frequency modulation. |
| 3. | of, pertaining to, or utilizing such a system. |
| fermium. |
| femtometer. |
| (in prescriptions) make a mixture. |
fer·mi·um  (fûr'mē-əm, fěr'-)  n. Symbol Fm A synthetic transuranic metallic element (atomic number 100) having 10 isotopes with mass numbers ranging from 248 to 257 and corresponding half-lives ranging from 0.6 minutes to approximately 100 days. See Table at element. [After Enrico Fermi.] |
| field marshal n. Abbr. FM An officer in some European armies, usually ranking just below the commander in chief. |
| Fm The symbol for the element fermium. |
| FM abbr.
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| frequency modulation n. Abbr. FM The encoding of a carrier wave by variation of its frequency in accordance with an input signal. |
Fm
The symbol for the element fermium.
| fermium (fûr'mē-əm) Pronunciation Key
Symbol Fm A synthetic, radioactive metallic element of the actinide series that is produced from plutonium or uranium. Its most stable isotope is Fm 257 with a half-life of approximately 100 days. Atomic number 100. See Periodic Table. |
| Fm
The symbol for fermium. |
| FM
Abbreviation of frequency modulation |
FM
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(2001-04-30)
fm networking
The country code for the Federated States of Micronesia.
Heavily used for vanity domains by FM radio stations.
(1999-01-27)
| Fm fermium |
FM
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Fm
(Fm), synthetic chemical element of the actinoid series of the periodic table, atomic number 100. Fermium (as the isotope fermium-255) is produced by the intense neutron irradiation of uranium-238 and was first positively identified by Albert Ghiorso and coworkers at Berkeley, Calif., in debris taken from the first thermonuclear or hydrogen-bomb test explosion (November 1952), in the South Pacific. All fermium isotopes are radioactive. Mixtures of the isotopes fermium-254 (3.24-hour half-life), fermium-255 (20.1-hour half-life), fermium-256 (2.7-hour half-life), and fermium-257 (80-day half-life) can be produced by the intensive slow-neutron irradiation of elements of lower atomic number, such as plutonium.
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