| flanking sequence | <molecular biology> Short DNA sequences bordering a transcription unit. Often these do not code for proteins. (18 Nov 1997) |
|---|---|
| flap | Anything broad and limber that hangs loose, or that is attached by one side or end and is easily moved; as, the flap of a garment. "A cartilaginous flap upon the opening of the larynx." (Sir T. Browne) 2. A hinged leaf, as of a table or shutter. 3. The motion of anything broad and loose, or a stroke or sound made with it; as, the flap of a sail or of a wing. 4. <veterinary> A disease in the lips of horses. Flap tile, a tile with a bent up portion, to turn a corner or catch a drip. <mechanics> Flap valve, a valve which opens and shuts upon one hinged side; a clack valve. Origin: OE. Flappe, flap, blow, bly-flap; cf. D. Flap, and E. Flap. Source: Websters Dictionary (01 Mar 1998) |
| flap amputation | An amputation in which flaps of the muscular and cutaneous tissues are made to cover the end of the bone. Synonym: flap operation. (05 Mar 2000) |
| flap gate | <ecology, equipment> A device which allows water to flow in only one direction through a culvert, can be used to allow water to drain out of a wetland during low tide while preventing water from entering the wetland during high tide. (09 Oct 1997) |
| flap operation | An amputation in which flaps of the muscular and cutaneous tissues are made to cover the end of the bone. Synonym: flap operation. (05 Mar 2000) |
| flapjack | 1. A fklat cake turned on the griddle while cooking; a griddlecake or pacake. 2. A fried dough cake containing fruit; a turnover. Source: Websters Dictionary (01 Mar 1998) |
| flapless amputation | An amputation without any tissue to cover the stump (05 Mar 2000) |
| flapper | 1. One who, or that which, flaps. 2. See Flipper. "The flapper of a porpoise. <zoology>" Flapper skate, a European skate (Raia intermedia). Source: Websters Dictionary (01 Mar 1998) |
| flapping tremor | <clinical sign, neurology> Abnormal muscle tremor consisting of involuntary jerking of the hands. May be seen in liver disease. (27 Sep 1997) |
| flare | <microscopy> Unwanted light in an optical instrument that arises by reflection at lens surfaces (including the observer's eyeglasses) and lens barrel, etc., and sometimes from lens aberration. Flare reduces image contrast and may form undesirable focused images and hot spots. Flare in a microscope is reduced by immersion of the condenser and objective lenses, anti-reflection (05 Aug 1998) |
| flare streaming | <cell biology> Phenomenon described in isolated cytoplasm of giant amoeba when the medium contains Ca and ATP. A loop of cytoplasm flows outward and then returns to the main mass the appearance is reminiscent of flares around the eclipsed sun. (18 Nov 1997) |
| flared teeth | <dentistry> A term used to indicate the position of the teeth. The upper teeth are flared lingually (toward the lip). (08 Jan 1998) |
| flarimeter | An obsolete device for use in evaluating cardiopulmonary fitness; pulse rate and blood pressure were measured during attempts to expire the vital capacity through calibrated orifices while maintaining a mouth pressure of 20 mm Hg. Origin: L. Flare, to blow, + G. Metron, measure (05 Mar 2000) |
| flash | 1. A pool. 2. <engineering> A reservoir and sluiceway beside a navigable stream, just above a shoal, so that the stream may pour in water as boats pass, and thus bear them over the shoal. <mechanics> Flash wheel, a paddle wheel made to revolve in a breast or curved water way, by which water is lifted from the lower to the higher level. Origin: OE. Flasche, flaske; cf. OF. Flache, F. Flaque. Source: Websters Dictionary (01 Mar 1998) |
| flash blindness | A temporary loss of vision produced when retinal light-sensitive pigments are bleached by light more intense than that to which the retina is physiologically adapted at that moment. (05 Mar 2000) |