The Collaborative International Dictionary of English v.0.48:

Poise \Poise\, n. [OE. pois, peis, OF. pois, peis, F. poids, fr.
   L. pensum a portion weighed out, pendere to weigh, weigh out.
   Cf. Avoirdupois, Pendant, Poise, v.] [Formerly written
   also peise.]
   1. Weight; gravity; that which causes a body to descend;
      heaviness. "Weights of an extraordinary poise." --Evelyn.
      [1913 Webster]

   2. The weight, or mass of metal, used in weighing, to balance
      the substance weighed.
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   3. The state of being balanced by equal weight or power;
      equipoise; balance; equilibrium; rest. --Bentley.
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   4. That which causes a balance; a counterweight.
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            Men of unbounded imagination often want the poise of
            judgment.                             --Dryden.
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   5. a dignified and self-confident manner; graceful composure
      and tact in handling difficult social situations.
      [PJC]

The Collaborative International Dictionary of English v.0.48:

Poise \Poise\, v. i.
   To hang in equilibrium; to be balanced or suspended; hence,
   to be in suspense or doubt.
   [1913 Webster]

         The slender, graceful spars
         Poise aloft in air.                      --Longfellow.
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The Collaborative International Dictionary of English v.0.48:

Poise \Poise\, v. t. [imp. & p. p. Poised, ; p. pr. & vb. n.
   Poising.] [OE. poisen, peisen, OF. & F. peser, to weigh,
   balance, OF. il peise, il poise, he weighs, F. il p[`e]se,
   fr. L. pensare, v. intens. fr. pendere to weigh. See Poise,
   n., and cf. Pensive.] [Formerly written also peise.]
   1. To balance; to make of equal weight; as, to poise the
      scales of a balance.
      [1913 Webster]

   2. To hold or place in equilibrium or equiponderance.
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            Nor yet was earth suspended in the sky;
            Nor poised, did on her own foundation lie. --Dryden.
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   3. To counterpoise; to counterbalance.
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            One scale of reason to poise another of sensuality.
                                                  --Shak.
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            To poise with solid sense a sprightly wit. --Dryden.
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   4. To ascertain, as by the balance; to weigh.
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            He can not sincerely consider the strength, poise
            the weight, and discern the evidence. --South.
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   5. To weigh (down); to oppress. [Obs.]
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            Lest leaden slumber peise me down to-morrow. --Shak.
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WordNet (r) 3.0 (2006):

poise
    n 1: a cgs unit of dynamic viscosity equal to one dyne-second
         per square centimeter; the viscosity of a fluid in which a
         force of one dyne per square centimeter maintains a
         velocity of 1 centimeter per second
    2: a state of being balanced in a stable equilibrium
    3: great coolness and composure under strain; "keep your cool"
       [syn: aplomb, assuredness, cool, poise, sang-froid]
    v 1: be motionless, in suspension; "The bird poised for a few
         moments before it attacked"
    2: prepare (oneself) for something unpleasant or difficult [syn:
       brace, poise]
    3: cause to be balanced or suspended
    4: hold or carry in equilibrium [syn: poise, balance]

Moby Thesaurus II by Grady Ward, 1.0:

194 Moby Thesaurus words for "poise":
   accommodate, action, actions, activity, acts, address, adjust,
   affectation, air, aplomb, arrogance, aspire, assurance,
   assuredness, back, balance, ballast, bearing, beck, beckon,
   become airborne, behavior, behavior pattern, behavioral norm,
   behavioral science, belief, body language, calmness, cancel,
   carriage, certitude, charade, chironomy, claw skyward,
   cocksureness, coequality, coextension, compensate, comportment,
   composure, conduct, confidence, confidentness, control, conviction,
   cool, coolness, coordinate, correspondence, counterbalance,
   counterpoise, countervail, courage, culture pattern, custom,
   dactylology, deaf-and-dumb alphabet, demeanor, deportment, dignity,
   diplomacy, doing, doings, dumb show, equability, equality,
   equalize, equanimity, equate, equation, equilibrium, equipoise,
   equipollence, equiponderance, equity, equivalence, equivalency,
   even, even up, evenness, faith, fit, float, fly, fly aloft,
   folkway, gain altitude, gesticulation, gesture, gesture language,
   gestures, goings-on, grace, guise, hand signal, hang, hover,
   hubris, identity, imperturbability, integrate, justice, kinesics,
   kite, leave the ground, level, level head, levelheadedness,
   levelness, likeness, maintien, manner, manners, method,
   methodology, methods, mien, modus vivendi, motion, motions,
   movement, movements, moves, observable behavior, overconfidence,
   oversureness, overweening, overweeningness, pantomime, par,
   parallelism, parity, pattern, plane, pomposity, port, pose,
   positiveness, possession, posture, practice, praxis, prepare,
   presence, presence of mind, pride, procedure, proceeding,
   proportion, reserve, restraint, sang-froid, security, sedateness,
   self-assurance, self-command, self-confidence, self-control,
   self-importance, self-possession, self-reliance, self-restraint,
   serenity, settled belief, shrug, sign language, soar,
   social science, spire, square, stabilitate, staidness, stance,
   stasis, steady, strike a balance, style, subjective certainty,
   support, sureness, surety, symmetry, tact, tactics, take off, tone,
   tranquillity, trust, uphold, way, way of life, ways,
   well-regulated mind, zoom