| Fc | centroid frequency; fraction/centrifuge; fragment, crystallizable [of immunoglobulin] |
|---|---|
| Fc' | a fragment of an immunoglobulin molecule produced by papain digestion |
| FW | Felix-Weil [reaction]; Folin-Wu [reaction]; fragment wound |
| HTF | heterothyrotropic factor; house tube feeding; HpaII tiny fragment |
| MFW | multiple fragment wounds |
| focal length | <microscopy> The distance from the optical centre of the lens to the focal point<microscopy> The focal length of an objective and its working distance are directly proportional. (05 Aug 1998) |
|---|---|
| leg length inequality | A condition in which one of a pair of legs fails to grow as long as the other. (12 Dec 1998) |
| length | 1. The longest, or longer, dimension of any object, in distinction from breadth or width; extent of anything from end to end; the longest line which can be drawn through a body, parallel to its sides; as, the length of a church, or of a ship; the length of a rope or line. 2. A portion of space or of time considered as measured by its length; often in the plural. "Large lengths of seas and shores." (Shak) "The future but a length behind the past." (Dryden) 3. The quality or state of being long, in space or time; extent; duration; as, some sea birds are remarkable for the length of their wings; he was tired by the length of the sermon, and the length of his walk. 4. A single piece or subdivision of a series, or of a number of long pieces which may be connected together; as, a length of pipe; a length of fence. 5. Detail or amplification; unfolding; continuance as, to pursue a subject to a great length. "May Heaven, great monarch, still augment your bliss. With length of days and every day like this." (Dryden) 6. Distance. "He had marched to the length of Exeter." (Clarendon) at length. At or in the full extent; without abbreviation; as, let the name be inserted at length. At the end or conclusion; after a long period. See Syn. Of At last, under Last. At arm's length. See Arm. Origin: OE. Lengthe, AS. Leng, fr. Land, long, long; akin to D. Lengte, Dan. Laengde, Sw. Langd, Icel. Lengd. See Long. Source: Websters Dictionary (01 Mar 1998) |
| length-breadth index | The ratio of the maximal breadth to the maximal length of the head, obtained by the formula: (breadth × 100)/length. Synonym: length-breadth index. (05 Mar 2000) |
| length-height index | The relation of the height to the length of the skull: (height × 100)/length. Synonym: height-length index, length-height index, transversovertical index. (05 Mar 2000) |
| length of stay | The period of confinement of a patient to a hospital or other health facility. (12 Dec 1998) |