The Collaborative International Dictionary of English v.0.48:

Navigate \Nav"i*gate\, v. t.
   1. To pass over in ships; to sail over or on; as, to navigate
      the Atlantic.
      [1913 Webster]

   2. To steer, direct, or manage in sailing; to conduct (ships)
      upon the water by the art or skill of seamen; as, to
      navigate a ship.
      [1913 Webster]

   3. To pass through, over, or around; -- used especially of a
      course having obstacles; as, to navigate all the randomly
      scattered tables to the far side of the room.
      [PJC]

The Collaborative International Dictionary of English v.0.48:

Navigate \Nav"i*gate\, v. i. [imp. & p. p. Navigated; p. pr. &
   vb. n. Navigating.] [L. navigatus, p. p. of navigare, v.t.
   & i.; navis ship + agere to move, direct. See Nave, and
   Agent.]
   1. To journey by water; to go in a vessel or ship; to perform
      the duties of a navigator; to use the waters as a highway
      or channel for commerce or communication; to sail.
      [1913 Webster]

            The Phenicians navigated to the extremities of the
            Western Ocean.                        --Arbuthnot.
      [1913 Webster]

   2. To direct or operate a vehicle, especially a ship or
      aircraft.
      [PJC]

   3. To pass through, over, or around; -- used especially of a
      course having obstacles; as, to navigate around all the
      randomly scattered tables to the far side of the room.
      [PJC]

WordNet (r) 3.0 (2006):

navigate
    v 1: travel on water propelled by wind or by other means; "The
         QE2 will sail to Southampton tomorrow" [syn: voyage,
         sail, navigate]
    2: act as the navigator in a car, plane, or vessel and plan,
       direct, plot the path and position of the conveyance; "Is
       anyone volunteering to navigate during the trip?"; "Who was
       navigating the ship during the accident?" [syn: navigate,
       pilot]
    3: direct carefully and safely; "He navigated his way to the
       altar"

Moby Thesaurus II by Grady Ward, 1.0:

86 Moby Thesaurus words for "navigate":
   aeroplane, airlift, airplane, allocate, assign, balloon,
   be airborne, boat, canoe, captain, carry sail, chart a course,
   circumnavigate, coast, collocate, con, cond, conn, coxswain, cross,
   cruise, deploy, direct, dispose, drift, emplace, ferry, fix, flit,
   fly, get a fix, glide, go by ship, go on shipboard, go to sea,
   guide, handle, have the conn, helm, home in on, hop, hover,
   hydroplane, install, jet, journey, localize, locate,
   make a passage, manage, motorboat, operate, pilot, pin down,
   pinpoint, place, ply, position, put in place, row, run, sail,
   sail round, sail the sea, sailplane, scull, seafare, seaplane,
   shape a course, situate, skipper, soar, spot, steam, steamboat,
   steer, take a voyage, take the air, take wing, traverse,
   triangulate, volplane, voyage, wing, yacht, zero in on