The Collaborative International Dictionary of English v.0.48:

Yaw \Yaw\, n. (Naut.)
   A movement of a vessel by which she temporarily alters her
   course; a deviation from a straight course in steering.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Yaw \Yaw\ (y[add]), v. i. [imp. & p. p. Yawed (y[add]d); p.
   pr. & vb. n. Yawing.] [Cf. Yew, v. i.]
   To rise in blisters, breaking in white froth, as cane juice
   in the clarifiers in sugar works.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Yaw \Yaw\, v. i. & t. [Cf. Prov. G. gagen to rock, gageln to
   totter, shake, Norw. gaga to bend backward, Icel. gagr bent
   back, gaga to throw the neck back.] (Naut.)
   To steer wild, or out of the line of her course; to deviate
   from her course, as when struck by a heavy sea; -- said of a
   ship.
   [1913 Webster]

         Just as he would lay the ship's course, all yawing
         being out of the question.               --Lowell.
   [1913 Webster]

WordNet (r) 3.0 (2006):

yaw
    n 1: an erratic deflection from an intended course [syn: yaw,
         swerve]
    v 1: be wide open; "the deep gaping canyon" [syn: gape,
         yawn, yaw]
    2: deviate erratically from a set course; "the yawing motion of
       the ship"
    3: swerve off course momentarily; "the ship yawed when the huge
       waves hit it"

Moby Thesaurus II by Grady Ward, 1.0:

146 Moby Thesaurus words for "yaw":
   aberrancy, aberration, about ship, back and fill, bank, bear away,
   bear off, bear to starboard, beat, beat about, bend, bias, box off,
   branching off, break, bring about, bring round, cant, cant round,
   cast, cast about, change course, change the heading,
   circuitousness, come about, corner, crab, crook, curve,
   declination, deflection, departure, detour, deviance, deviancy,
   deviation, deviousness, digression, dip, discursion, divagation,
   divarication, divergence, diversion, dogleg, double,
   double a point, drift, drift off course, drifting, drive, errantry,
   excursion, excursus, exorbitation, fall down, feather, fetch about,
   fetch away, fishtail, flounder, gape, go about, gybe, hairpin,
   heave, heave round, hobbyhorse, horizontal axis, indirection, jibe,
   jibe all standing, loop, lurch, make heavy weather, make leeway,
   miss stays, obliquity, pay off, pererration, pitch, pitch and toss,
   plow, plunge, ply, porpoise, pound, pull out, pull up, push down,
   put about, put back, rambling, rear, reel, rock, roll,
   round a point, sag, scend, sheer, shift, shifting, shifting course,
   shifting path, sideslip, skew, skid, slant, slew, spin, spiral,
   straying, stunt, swag, sway, sweep, swerve, swerving, swing,
   swing round, swing the stern, swinging, tack, throw about, tilt,
   tilter, toss, toss and tumble, tumble, turn, turn back, turning,
   twist, undulate, variation, veer, wallow, wandering, warp, wear,
   wear ship, welter, wind, yaw off, zigzag