The Collaborative International Dictionary of English v.0.48:

Viaticum \Vi*at"i*cum\, n. [L., from viaticus, a. See Viatic.]
   1. (Rom. Antiq.) An allowance for traveling expenses made to
      those who were sent into the provinces to exercise any
      office or perform any service.
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   2. Provisions for a journey. --Davies (Wit's Pilgr.).
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   3. (R. C. Ch.) The communion, or eucharist, when given to
      persons in danger of death.
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