Source : Webster's Revised Unabridged Dictionary (1913)

Ration \Ra"tion\, n. [F., fr. L. ratio a reckoning, calculation,
   relation, reference, LL. ratio ration. See {Ratio}.]
   1. A fixed daily allowance of provisions assigned to a
      soldier in the army, or a sailor in the navy, for his
      subsistence.

   Note: Officers have several rations, the number varying
         according to their rank or the number of their
         attendants.

   2. Hence, a certain portion or fixed amount dealt out; an
      allowance; an allotment.

Ration \Ra"tion\, v. t.
   To supply with rations, as a regiment.

Source : WordNet®

ration
     n 1: the food allowance for one day (especially for service
          personnel); "the rations should be nutritionally
          balanced"
     2: a fixed portion that is allotted (especially in times of
        scarcity)

ration
     v 1: restrict the consumption of a relatively scarce commodity,
          as during war; "Bread was rationed during the siege of
          the city"
     2: distribute in rations, as in the army; "Cigarettes are
        rationed" [syn: {ration out}]