Pronunciation: (drift),[key] —n. 1. a driving movement or force; impulse; impetus; pressure.
2. Navig.(of a ship) the component of the movement that is due to the force of wind and currents.
3. Oceanog.a broad, shallow ocean current that advances at the rate of 10 to 15 mi. (16 to 24 km) a day.
4. Naut. a. the flow or the speed in knots of an ocean current.
b. the distance between the end of a rope and the part in use.
c. the distance between two blocks in a tackle.
d. the difference in diameter between two parts, one of which fits within the other, as a mast and its mast hoops, or a treenail and its hole.
5. Aeron.the deviation of an aircraft from a set course due to cross winds.
6. the course along which something moves; tendency; aim: The drift of political events after the war was toward chaos. 7. a meaning; intent; purport: the drift of a statement. 8. something driven, as animals, rain, etc.
9. a heap of any matter driven together.
10. a snowdrift.
11. Geol.See glacial drift. 12. the state or process of being driven.
13. overbearing power or influence.
14. Mil.a tool used in charging an ordnance piece.
15. Electronics. a. a gradual change in some operating characteristic of a circuit, tube, or other electronic device, either during a brief period as an effect of warming up or during a long period as an effect of continued use.
b. the movement of charge carriers in a semiconductor due to the influence of an applied voltage.
16. Ling.gradual change in the structure of a language.
17. Mach. a. Also called driftpin. a round, tapering piece of steel for enlarging holes in metal, or for bringing holes in line to receive rivets or bolts.
b. a flat, tapered piece of steel used to drive tools with tapered shanks, as drill bits, from their holders.
18. Civ. Engin.a secondary tunnel between two main tunnels or shafts.
19. Mining.an approximately horizontal passageway in underground mining.
20. Physics.the movement of charged particles under the influence of an electric field.
21. Aerospace.the gradual deviation of a rocket or guided missile from its intended trajectory.
22. Mech.displacement of the gimbals of a gyroscope due to friction on bearings, unbalance of the gyroscope's mass or other imperfections.
23. the thrust of an arched structure.
24. Dentistry.a shift of the teeth from their normal position in the dental arch.
25. Western U.S.a flock of animals or birds.
—v.i. 1. to be carried along by currents of water or air, or by the force of circumstances.
2. to wander aimlessly: He drifts from town to town. 3. to be driven into heaps, as by the wind: drifting sand. 4. to deviate or vary from a set course or adjustment.
—v.t. 1. to carry along: The current drifted the boat to sea. 2. to drive into heaps: The wind drifted the snow. 3. Mach. a. to enlarge (a punched or drilled hole) with a drift.
b. to align or straighten (holes, esp. rivet holes) with a drift.
4. drift off,to fall asleep gradually.