The Collaborative International Dictionary of English v.0.48:

Continental drift \Continental drift\
   the movements of continents relative to each other across the
   Earth's surface; see plate tectonics.
   [PJC]

The Collaborative International Dictionary of English v.0.48:

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 [self] away with drift of his
            wings.                                --King
                                                  Alisaunder
                                                  (1332).
      [1913 Webster]

   2. The act or motion of drifting; the force which impels or
      drives; an overpowering influence or impulse.
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            A bad man, being under the drift of any passion,
            will follow the impulse of it till something
            interpose.                            --South.
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   3. Course or direction along which anything is driven;
      setting. "Our drift was south." --Hakluyt.
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   4. The tendency of an act, argument, course of conduct, or
      the like; object aimed at or intended; intention; hence,
      also, import or meaning of a sentence or discourse; aim.
      [1913 Webster]

            He has made the drift of the whole poem a compliment
            on his country in general.            -- Addison.
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            Now thou knowest my drift.            --Sir W.
                                                  Scott.
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   5. That which is driven, forced, or urged along; as:
      (a) Anything driven at random. "Some log . . . a useless
          drift." --Dryden.
      (b) A mass of matter which has been driven or forced
          onward together in a body, or thrown together in a
          heap, etc., esp. by wind or water; as, a drift of
          snow, of ice, of sand, and the like.
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                Drifts of rising dust involve the sky. -- Pope.
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                We got the brig a good bed in the rushing drift
                [of ice].                         --Kane.
      (c) A drove or flock, as of cattle, sheep, birds. [Obs.]
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                Cattle coming over the bridge (with their great
                drift doing much damage to the high ways). --
                                                  Fuller.
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   6. (Arch.) The horizontal thrust or pressure of an arch or
      vault upon the abutments. [R.] --Knight.
      [1913 Webster]

   7. (Geol.) A collection of loose earth and rocks, or
      boulders, which have been distributed over large portions
      of the earth's surface, especially in latitudes north of
      forty degrees, by the agency of ice.
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   8. In South Africa, a ford in a river.
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   9. (Mech.) A slightly tapered tool of steel for enlarging or
      shaping a hole in metal, by being forced or driven into or
      through it; a broach.
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   10. (Mil.)
       (a) A tool used in driving down compactly the composition
           contained in a rocket, or like firework.
       (b) A deviation from the line of fire, peculiar to oblong
           projectiles.
           [1913 Webster]

   11. (Mining) A passage driven or cut between shaft and shaft;
       a driftway; a small subterranean gallery; an adit or
       tunnel.
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   12. (Naut.)
       (a) The distance through which a current flows in a given
           time.
       (b) The angle which the line of a ship's motion makes
           with the meridian, in drifting.
       (c) The distance to which a vessel is carried off from
           her desired course by the wind, currents, or other
           causes.
       (d) The place in a deep-waisted vessel where the sheer is
           raised and the rail is cut off, and usually
           terminated with a scroll, or driftpiece.
       (e) The distance between the two blocks of a tackle.
           [1913 Webster]

   13. The difference between the size of a bolt and the hole
       into which it is driven, or between the circumference of
       a hoop and that of the mast on which it is to be driven.
       [1913 Webster]

   14. (Phys. Geog.) One of the slower movements of oceanic
       circulation; a general tendency of the water, subject to
       occasional or frequent diversion or reversal by the wind;
       as, the easterly drift of the North Pacific.
       [Webster 1913 Suppl.]

   15. (A["e]ronautics) The horizontal component of the pressure
       of the air on the sustaining surfaces of a flying
       machine. The lift is the corresponding vertical
       component, which sustains the machine in the air.
       [Webster 1913 Suppl.]

   Note: Drift is used also either adjectively or as the first
         part of a compound. See Drift, a.
         [1913 Webster]

   Drift of the forest (O. Eng. Law), an examination or view
      of the cattle in a forest, in order to see whose they are,
      whether they are commonable, and to determine whether or
      not the forest is surcharged. --Burrill. [1913 Webster]

   continental drift (Geology), the very slow (ca. 1-5 cm per
      year) movement of the continents and parts of continents
      relative to each other and to the points of upwelling of
      magma in the viscous layers beneath the continents; --
      causing, for example, the opening of the South Atlantic
      Ocean by the movement of Africa and South America away
      from each other. See also plate tectonics.
      [PJC]

WordNet (r) 3.0 (2006):

continental drift
    n 1: the gradual movement and formation of continents (as
         described by plate tectonics)

The Free On-line Dictionary of Computing (30 December 2018):

continental drift

    Very, very slow.  In 1980 David Turner remarked that
   KRC ran "at the speed of the continental drift".

   (1994-12-06)