Source : Webster's Revised Unabridged Dictionary (1913)

Dotage \Do"tage\, n. [From {Dote}, v. i.]
   1. Feebleness or imbecility of understanding or mind,
      particularly in old age; the childishness of old age;
      senility; as, a venerable man, now in his dotage.

            Capable of distinguishing between the infancy and
            the dotage of Greek literature.       --Macaulay.

   2. Foolish utterance; drivel.

            The sapless dotages of old Paris and Salamanca. --
                                                  Milton.

   3. Excessive fondness; weak and foolish affection.

            The dotage of the nation on presbytery. -- Bp.
                                                  Burnet.

Source : WordNet®

dotage
     n : mental infirmity as a consequence of old age; sometimes
         shown by foolish infatuations [syn: {second childhood}, {senility}]