The Collaborative International Dictionary of English v.0.48:

Plight \Plight\, v. t. [imp. & p. p. Plighted; p. pr. & vb. n.
   Plighting.] [AS. plihtan to expose to danger, pliht
   danger;cf. D. verplichten to oblige, engage, impose a duty,
   G. verpflichten, Sw. f["o]rplikta, Dan. forpligte. See
   Plight, n.]
   1. To pledge; to give as a pledge for the performance of some
      act; as, to plight faith, honor, word; -- never applied to
      property or goods. " To do them plighte their troth."
      --Piers Plowman.
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            He plighted his right hand
            Unto another love, and to another land. --Spenser.
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            Here my inviolable faith I plight.    --Dryden.
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   2. To promise; to engage; to betroth.
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            Before its setting hour, divide
            The bridegroom from the plighted bride. --Sir W.
                                                  Scott.
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The Collaborative International Dictionary of English v.0.48:

Plight \Plight\, obs.
   imp. & p. p. of Plight, to pledge. --Chaucer.
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The Collaborative International Dictionary of English v.0.48:

Plight \Plight\, obs.
   imp. & p. p. of Pluck. --Chaucer.
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The Collaborative International Dictionary of English v.0.48:

Plight \Plight\, v. t. [OE. pliten; probably through Old French,
   fr. LL. plectare, L. plectere. See Plait, Ply.]
   To weave; to braid; to fold; to plait.[Obs.] "To sew and
   plight." --Chaucer.
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         A plighted garment of divers colors.     --Milton.
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The Collaborative International Dictionary of English v.0.48:

Plight \Plight\, n.
   A network; a plait; a fold; rarely a garment. [Obs.] "Many a
   folded plight." --Spenser.
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The Collaborative International Dictionary of English v.0.48:

Plight \Plight\, n. [OE. pliht danger, engagement, AS. pliht
   danger, fr. ple['o]n to risk; akin to D. plicht duty, G.
   pflicht, Dan. pligt. [root]28. Cf. Play.]
   1. That which is exposed to risk; that which is plighted or
      pledged; security; a gage; a pledge. "That lord whose hand
      must take my plight." --Shak.
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   2. [Perh. the same word as plight a pledge, but at least
      influenced by OF. plite, pliste, ploit, ploi, a condition,
      state; cf. E. plight to fold, and F. pli a fold, habit,
      plier to fold, E. ply.] Condition; state; -- risk, or
      exposure to danger, often being implied; as, a luckless
      plight. "Your plight is pitied." --Shak.
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            To bring our craft all in another plight --Chaucer.
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WordNet (r) 3.0 (2006):

plight
    n 1: a situation from which extrication is difficult especially
         an unpleasant or trying one; "finds himself in a most
         awkward predicament"; "the woeful plight of homeless
         people" [syn: predicament, quandary, plight]
    2: a solemn pledge of fidelity [syn: plight, troth]
    v 1: give to in marriage [syn: betroth, engage, affiance,
         plight]
    2: promise solemnly and formally; "I pledge that I will honor my
       wife" [syn: pledge, plight]

Moby Thesaurus II by Grady Ward, 1.0:

174 Moby Thesaurus words for "plight":
   adverse circumstances, adversity, affiance, affliction,
   aggravation, annoyance, assurance, assure, avouch, avouchment,
   baffle, bafflement, bearings, become engaged, betroth,
   bewilderment, bind, blight, bother, box, breakers ahead, bummer,
   cardhouse, care, case, catch-22, cause for alarm, circumstance,
   circumstances, clutch, complication, condition, confoundment,
   confusion, contract, contract an engagement, corner, countersign,
   covenant, crisis, cross, crunch, curse, danger, dangerous ground,
   difficulties, difficulty, dilemma, discomposure, disconcert,
   disconcertedness, disconcertion, disconcertment, disturbance,
   downer, embarrassing position, embarrassment, emergency,
   endangerment, engage, engagement, enigma, estate, extremity, faith,
   fine how-do-you-do, fix, footing, gaping chasm, gathering clouds,
   guarantee, hard knocks, hard life, hard lot, hardcase, hardship,
   hazard, hell to pay, hobble, hole, hot water, house of cards,
   how-do-you-do, imbroglio, imperilment, irritation, jam, jeopardy,
   location, lot, make a promise, menace, mess, mix, modality, mode,
   morass, mystery, nonplus, oath, parlous straits, parole, pass,
   peril, perplexity, perturbation, pickle, pinch, place, pledge,
   position, posture, pother, predicament, pressure, pretty pass,
   pretty pickle, pretty predicament, problem, promise,
   publish the banns, puzzle, puzzlement, quagmire, quandary,
   quicksand, rank, riddle, rigor, risk, rocks ahead, scrape,
   sea of troubles, situation, slough, solemn declaration, spot,
   squeeze, standing, state, station, status, stew, sticky wicket,
   storm clouds, strait, straits, stress, stress of life, swamp,
   swear, thin ice, threat, tight spot, tight squeeze, tightrope,
   trial, tribulation, tricky spot, troth, trouble, troubles,
   unassuredness, underwrite, unholy mess, upset, vale of tears,
   vicissitude, vouch, vow, warrant, warranty, word, word of honor