Source : Webster's Revised Unabridged Dictionary (1913)

Dais \Da"is\ (d[=a]"[i^]s), n. [OE. deis, des, table, dais, OF.
   deis table, F. dais a canopy, L. discus a quoit, a dish (from
   the shape), LL., table, fr. Gr. ? a quoit, a dish. See
   {Dish}.]
   1. The high or principal table, at the end of a hall, at
      which the chief guests were seated; also, the chief seat
      at the high table. [Obs.]

   2. A platform slightly raised above the floor of a hall or
      large room, giving distinction to the table and seats
      placed upon it for the chief guests.

   3. A canopy over the seat of a person of dignity. [Obs.]
      --Shiply.

Source : WordNet®

dais
     n : a platform raised above the surrounding level to give
         prominence to the person on it [syn: {podium}, {pulpit},
         {rostrum}, {ambo}, {stump}, {soapbox}]