| flung |
past tense and part participle of fling. |
| flunk |
(informal) to be unsuccessful; fail, as a student in an examination or course. [3 definitions] |
| flunk out |
(informal) to be dismissed from a school because of failing grades. |
| flunky |
one who does unskilled, menial, or trivial tasks. [3 definitions] |
| fluor |
calcium fluoride; fluorite. [2 definitions] |
| fluoresce |
to exhibit, produce, or undergo radiation, esp. to emit visible light during or after exposure to radiation. |
| fluorescence |
the giving off of electromagnetic radiation, esp. in the form of visible light, during or after exposure to radiation from another source such as ultraviolet light or x-rays. [2 definitions] |
| fluorescent |
able to react to external radiation by emitting electromagnetic radiation, usu. in the form of visible light. |
| fluorescent lamp |
a glass tube with a fluorescent coating on the inside that gives off light when the mercury vapor in the tube is bombarded with a stream of electrons. |
| fluoridate |
to add a fluoride to (a water supply) in order to decrease or prevent tooth decay. |
| fluoridation |
the introduction of controlled amounts of a fluoride into a public water supply as a preventative of tooth decay. |
| fluoride |
a chemical compound that contains fluorine as one of its elements. |
| fluorinate |
to treat, combine, or inject with fluorine. [2 definitions] |
| fluorine |
an extremely reactive chemical element of the halogen group that has nine protons in each nucleus and that occurs naturally only in compounds such as fluoride salts, but that can be isolated in pure form as a yellowish, highly toxic gas. (symbol: F) |
| fluorite |
a transparent, crystalline, and variously colored mineral that is the chief source of fluorine; calcium fluoride. |
| fluoro- |
fluorine. [2 definitions] |
| fluorocarbon |
any of various organic chemical compounds resulting from the substitution of fluorine for hydrogen in a hydrocarbon, used in refrigeration, lubrication, plastic and resin manufacture, as a fire extinguisher, and formerly as the propellant in aerosol cans. |
| fluorometer |
a device used to detect and measure the wavelength and intensity of fluorescence. |
| fluoroscope |
a fluorescent screen used with x-rays or other radiation for viewing the internal structure of opaque objects such as the human body. |
| fluoroscopy |
examination by means of a fluoroscope. |
| fluorosis |
an abnormal condition, such as mottling of teeth, caused by excess intake of fluoride compounds. |