drift

drift
1. A gradual movement, as from an original position. 2. A gradual change in the value of a random variable over time as a result of various factors, some random and some systematic effects of trend, manipulation, etc.
- antigenic d. the process of “evolutionary” changes in molecular structure of DNA/RNA in microorganisms during their passage from one host to another; it may be due to recombination, deletion, or insertion of genes, point mutations or combinations of these events; it leads to alteration (usually slow and progressive) in the antigenic composition, and therefore in the immunologic responses of individuals and populations to exposure to the microorganism concerned; common with influenzavirus.
- genetic d. a change in the frequencies of genetic traits or allele frequencies over generations.
- pure random d. that which has random components only with an average value of zero and no systematic effects. Brownian movement in a still container shows pure random d. but in the Mississippi shows a steady downstream tendency.

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drift 'drift n
1) movement of a tooth in the dental arch
2) GENETIC DRIFT
drift vi

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(drift) [A.S. drifan to drive] 1. slow movement away from the normal or original position. 2. a chance variation, as in gene frequency between populations; the smaller the population, the greater the chance of random variations. Called also genetic d. or random genetic d.

Medical dictionary. 2011.

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  • Drift — may mean: Contents 1 Film and literature 2 Geography 3 Industry …   Wikipedia

  • Drift — Drift, n. [From {drive}; akin to LG. & D. drift a driving, Icel. drift snowdrift, Dan. drift, impulse, drove, herd, pasture, common, G. trift pasturage, drove. See {Drive}.] 1. A driving; a violent movement. [1913 Webster] The dragon drew him… …   The Collaborative International Dictionary of English

  • drift — [ drift ] n. m. • 1842; mot angl. ♦ Anglic. Géol. Dépôt laissé par le recul d un glacier. ● drift nom masculin (anglais drift, poussée) Transistor dans lequel la partie de la base en contact avec l émetteur est plus riche en électrons que le… …   Encyclopédie Universelle

  • drift — drift·age; drift; drift·er; drift·ing·ly; drift·land; drift·less; drift·less·ness; drift·man; spin·drift; spoon·drift; …   English syllables

  • Drift — Drift, a. That causes drifting or that is drifted; movable by wind or currents; as, drift currents; drift ice; drift mud. Kane. [1913 Webster] {Drift anchor}. See {Sea anchor}, and also {Drag sail}, under {Drag}, n. {Drift epoch} (Geol.), the… …   The Collaborative International Dictionary of English

  • Drift — („Treiben“) bezeichnet: in ländlichen Gebieten einen Weg für den Viehtrieb in der Messtechnik einen sich kontinuierlich verändernden Messfehler in der Nachrichtentechnik eine langsame Änderung im Signalweg, siehe Drift (Nachrichtentechnik) in der …   Deutsch Wikipedia

  • Drift — Sf durch Wind erzeugte Strömung; unkontrolliertes Treiben per. Wortschatz fach. (14. Jh.) Entlehnung. Ursprünglich niederdeutsches Seemannswort aus einem ti Abstraktum zu treiben, also Entsprechung zu nhd. Trift. Neuere Bedeutungen hängen in der… …   Etymologisches Wörterbuch der deutschen sprache

  • drift — [drift] n. [ME (akin to ON & MDu drift, OHG trift) < OE drifan, DRIVE] 1. an act or instance of being driven or carried along, as by a current of air or water or by circumstances 2. the course on which something is directed or driven 3. the… …   English World dictionary

  • drift — drȉft m <N mn drìftovi> DEFINICIJA 1. pom. bočno zanošenje broda (zbog vjetra, morske struje itd.) 2. geogr. morska struja koja nastaje pod stalnim naletima vjetra 3. pren. predmeti (podrtine broda, ledeni bregovi itd.) koji plutaju morem… …   Hrvatski jezični portal

  • Drift — (Байрон Бей,Австралия) Категория отеля …   Каталог отелей

  • Drift — Drift, v. i. [imp. & p. p. {Drifted}; p. pr. & vb. n. {Drifting}.] 1. To float or be driven along by, or as by, a current of water or air; as, the ship drifted astern; a raft drifted ashore; the balloon drifts slowly east. [1913 Webster] We… …   The Collaborative International Dictionary of English

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