The Collaborative International Dictionary of English v.0.48:

Endanger \En*dan"ger\, v. t. [imp. & p. p. Endangered; p. pr.
   & vb. n. Endangering.]
   1. To put to hazard; to bring into danger or peril; to expose
      to loss or injury; as, to endanger life or peace.
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            All the other difficulties of his reign only
            exercised without endangering him.    --Burke.
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   2. To incur the hazard of; to risk. [Obs.]
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            He that turneth the humors back . . . endangereth
            malign ulcers.                        --Bacon.
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