Source : Webster's Revised Unabridged Dictionary (1913)

Peril \Per"il\, n. [F. p['e]ril, fr. L. periculum, periclum,
   akin to peritus experienced, skilled, and E. fare. See
   {Fare}, and cf. {Experience}.]
   Danger; risk; hazard; jeopardy; exposure of person or
   property to injury, loss, or destruction.

         In perils of waters, in perils of robbers. --2 Cor. xi.
                                                  26.

         Adventure hard With peril great achieved. --Milton.

   {At}, or {On}, {one's peril}, with risk or danger to one; at
      the hazard of. ``On thy soul's peril.'' --Shak.

   Syn: Hazard; risk; jeopardy. See {Danger}.

Peril \Per"il\, v. t. [imp. & p. p. {Periled}or {Perilled}; p.
   pr. & vb. n. {Periling} or {Perilling}.]
   To expose to danger; to hazard; to risk; as, to peril one's
   life.

Peril \Per"il\, v. i.
   To be in danger. [Obs.] --Milton.

Source : WordNet®

peril
     n 1: a source of danger; a possibility of incurring loss or
          misfortune; "drinking alcohol is a health hazard" [syn:
          {hazard}, {jeopardy}, {risk}]
     2: a state of danger involving risk [syn: {riskiness}]
     3: 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},
         {danger}]

peril
     v 1: pose a threat to; present a danger to; "The pollution is
          endangering the crops" [syn: {endanger}, {jeopardize}, {jeopardise},
           {menace}, {threaten}, {imperil}]
     2: put in a dangerous, disadvantageous, or difficult position
        [syn: {queer}, {expose}, {scupper}, {endanger}]