The Collaborative International Dictionary of English v.0.48:

Risk \Risk\, n. [F. risque; cf. It. risco, risico, rischio, Pg.
   risco, Sp. riesgo, and also Sp. risco a steep rock; all
   probably fr. L. resceare to cut off; pref. re- re- + secare
   to cut; -- the word having been probably first used among
   sailors. See Section.]
   1. Hazard; danger; peril; exposure to loss, injury, or
      destruction.
      [1913 Webster]

            The imminent and constant risk of assassination, a
            risk which has shaken very strong nerves.
                                                  --Macaulay.
      [1913 Webster]

   2. (Com.) Hazard of loss; liabillity to loss in property.
      [1913 Webster]

   To run a risk, to incur hazard; to encounter danger.
      [1913 Webster]

   Syn: Danger; hazard; peril; jeopardy; exposure. See Danger.
        [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Risk \Risk\, v. t. [imp. & p. p. Risked; p. pr. & vb. n.
   Risking.] [CF. F. risquer. See Risk, n.]
   1. To expose to risk, hazard, or peril; to venture; as, to
      risk goods on board of a ship; to risk one's person in
      battle; to risk one's fame by a publication.
      [1913 Webster]

   2. To incur the risk or danger of; as, to risk a battle.
      [1913 Webster]

   Syn: To hazard; peril; endanger; jeopard.
        [1913 Webster]

WordNet (r) 3.0 (2006):

risk
    n 1: a source of danger; a possibility of incurring loss or
         misfortune; "drinking alcohol is a health hazard" [syn:
         hazard, jeopardy, peril, risk, endangerment]
    2: a venture undertaken without regard to possible loss or
       injury; "he saw the rewards but not the risks of crime";
       "there was a danger he would do the wrong thing" [syn:
       risk, peril, danger]
    3: the probability of becoming infected given that exposure to
       an infectious agent has occurred [syn: risk, risk of
       infection]
    4: the probability of being exposed to an infectious agent [syn:
       risk, risk of exposure]
    v 1: expose to a chance of loss or damage; "We risked losing a
         lot of money in this venture"; "Why risk your life?"; "She
         laid her job on the line when she told the boss that he was
         wrong" [syn: risk, put on the line, lay on the line]
    2: take a risk in the hope of a favorable outcome; "When you buy
       these stocks you are gambling" [syn: gamble, chance,
       risk, hazard, take chances, adventure, run a risk,
       take a chance]

Moby Thesaurus II by Grady Ward, 1.0:

175 Moby Thesaurus words for "risk":
   accident, accidentality, actuarial calculation, admit of,
   adventitiousness, adventure, be liable, be subjected to, beard,
   bet, bid fair to, brave, break, breakers ahead, buy in, buy into,
   calculated risk, cardhouse, casualness, cause for alarm, chance,
   chance it, compromise, confront, court destruction, crisis, danger,
   dangerous ground, dare, defy, defy danger, destiny, desultoriness,
   emergency, encounter, encounter danger, endanger, endangerment,
   expose, exposure, face, face up to, fate, financier, flier,
   flukiness, forget the odds, fortuitousness, fortuity, fortune,
   gamble, gamble on, gamble with, gaping chasm, gathering clouds,
   good fortune, good luck, hap, happenstance, happy chance, hazard,
   heedless hap, house of cards, how they fall, imperil, imperilment,
   incur danger, indeterminacy, indeterminateness, infirmity,
   insecurity, insolidity, instability, insubstantiality, invest,
   invest in, investment, jeopard, jeopardize, jeopardy,
   law of averages, lay open, lay out money, liability, liableness,
   lie under, lot, luck, make an investment, make book, meet, menace,
   moira, openness, opportunity, pass, peril, perilousness, pinch,
   place, play, play with fire, plight, plow back into, plunge,
   precariousness, predicament, predict, prime investment,
   principle of indeterminacy, probability, problematicness,
   prognosticate, put, put in danger, put in jeopardy, quicksand,
   random sample, reinvest, rely on fortune, riskiness, rocks ahead,
   run a chance, run of luck, run the chance, run the risk,
   serendipity, set at hazard, shakiness, shiftiness, shiftingness,
   sink, sink money in, slipperiness, speculate, speculation,
   speculativeness, stand a chance, stand fair to, stand to gain,
   stand to lose, statistical probability, storm clouds, strait,
   take a chance, take a flier, take chances, tempt Providence,
   tempt fortune, the breaks, theory of probability, thin ice, threat,
   ticklishness, treacherousness, treachery, trust to chance,
   try the chance, unauthenticity, unauthoritativeness, uncertainty,
   uncertainty principle, undependability, unfaithworthiness,
   unreliability, unsolidity, unsoundness, unsteadfastness,
   unsteadiness, unsubstantiality, unsureness, untrustworthiness,
   venture, wager, whatever comes



Bouvier's Law Dictionary, Revised 6th Ed (1856):

RISK. A danger, a peril to which a thing is exposed. The subject will be
divided by considering, 1. Risks with regard to insurances. 2. Risks in the
contracts of sale, barter, &c.
     2.-Sec. 1. In the contract of insurance, the insurer takes upon him
the risks to which the subject of the insurance is exposed, and agrees to
indemnify the insured when a loss occurs. This is equally the case in marine
and terrestrial insurance. But as the rules which govern these several
contracts are not the same, the subject of marine risks will be considered,
and, afterwards, of terrestrial risks.
     3.-1st. Marine risks are perils which are incident to a sea voyage; 1
Marsh. Ins. 215; or those fortuitous events which may happen in the course
of the voyage. Poth. Contr. d'assur. n. 49; Pardes. Dr. Com. n. 770. It will
be proper to consider, 1. Their nature. 2. Their duration.
     4.-1. The nature of the risks usually insured against. These risks
may be occasioned by storms, shipwreck, jetsam, prize, pillage, fire, war,
reprisals, detention by foreign governments, contribution to losses
experienced for the common benefit, or for expenses which would not have
taken place if it had not been for such events. But the insurer may by
special contract limit his responsibility for these risks. He may insure
against all risks, or only against enumerated risks; for the benefit of
particular persons, or for whom it may concern. 2 Wash. C. C. R. 346; 1
John. Cas. 337; 2 John. Cas. 480 1 Pet. 151 2 Mass.,365; 8 Mass. 308. The
law itself has made some exceptions founded on public policy, which require
that in certain cases men shall not be permitted to protect themselves
against some particular perils by insurance; among these are, first, that no
man can insure any loss or damage proceeding directly from his own fault. 1
John. Cas. 337; Poth. h.t. n. 65; Pard. h.t. n. 771; Marsh. Ins. 215.
Secondly, nor can be insure risks or perils of the sea, upon a trade
forbidden by the laws. Thirdly, the risks excluded by the usual memorandum
(q.v.) contained in the policy. Marsh. Ins. 221.
     5. As the insurance is upon maritime risks, the accidents must have
happened on the sea, unless the agreement include other risks. The loss by
accidents which might happen on land in the course of the voyage, even when
the unloading may have been authorized by the policy, or is required by
local regulations, as where they are necessary for sanitary measures, is not
borne by the insurer. Pard. Dr. Com. n. 770.
     6.-2. As to the duration of the risk. The commencement and end of the
risk depend upon the words of the policy. The insurer may take and modify
what risks he pleases. The policy may be on a voyage out, or a voyage in, or
it may be for part of the route, or for a limited time, or from port to
port. See 3 Kent, Com. 254; Pard. Dr. Com. n. 775; Marsh. 246; 1 Binn. 592.
The duration of the risk on goods is considered in Marsh. Ins. 247 a; on
ships, p. 280; on freight, p. 278, and 12 Wheat. 383.
     7.-2d. In insurances against fire, the risks and losses insured
against, are all losses or damages by fire; but, as in cases of marine
insurances, this may be limited as to the things insured, or as to the cause
or occasion of the accident, and many policies exclude fires caused by a mob
or the enemies of the commonwealth. The duration of the policy is limited by
its own provisions.
     8.-3d. In insurances on lives, the risks are the death of the party
from whatever cause, but in general the following risks are excepted,
namely: 1. Death abroad or in a district excluded by the terms of the
policy. 2. Entering into the naval or military service without the consent
of the insurer. 3. Death by suicide. 4. Death by duelling. 5. Death by the
hands of justice. See Insurance on lives. The duration of the risks is
limited by the terms of the policy.
     9.-Sec. 2. As a general rule, whenever the sale has been completed;
the risk of loss of the things sold is upon the buyer; but until it is
complete, and while something remains to be done by either party, in
relation to it, the risk is on the seller; as, if the goods are to be
weighed or measured. See Sale.
    10. In sales, the risks to which property is exposed and the loss which
may occur, before the contract is fully complete, must be borne by him in
whom the title resides: when the bargain, therefore, is made and rendered
binding by giving earnest, or by part payment, or part delivery, or by a
compliance with the requisitions of the statute of frauds, the property, and
with it the risk, attaches to the purchaser. 2 Kent, Com. 392.
    11. In Louisiana, as soon as the contract of sale is completed, the
thing sold is at the risk of the buyer, but with the following
modifications: Until the thing sold is delivered to the buyer, the seller is
obliged to guard it as a faithful administrator, and if through his want of
care, the thing is destroyed, or its value diminished, the seller is
responsible for the loss. He is released from this degree of care, when the
buyer delays obtaining the possession: but he is still liable for any injury
which the thing sold may sustain through gross neglect on his part. If it
is the seller who delays to deliver the thing, and it be destroyed, even by
a fortuitous event, it is be who sustains the loss, unless it appears that
the fortuitous event would equally have occasioned the destruction of the
thing in the buyer's possession, after delivery. Art. 2442-2445. For the
rules of the civil law on this subject, see Inst. 2, 1, 41; Poth. Contr. de
Vente, 4eme partie, n. 308, et seq.