Source : Webster's Revised Unabridged Dictionary (1913)

Thursday \Thurs"day\, n. [OE. [thorn]ursdei, [thorn]orsday, from
   the Scand. name Thor + E. day. Icel. [thorn][=o]rr Thor, the
   god of thunder, is akin to AS. [thorn]unor thunder; D.
   Donderdag Thursday, G. Donnerstag, Icel. [thorn][=o]rsdagr,
   Sw. & Dan. Torsdag. [root]52. See {Thor}, {Thunder}, and
   {Day}.]
   The fifth day of the week, following Wednesday and preceding
   Friday.

   {Holy Thursday}. See under {Holy}.

Source : WordNet®

Thursday
     n : the fifth day of the week; the fourth working day [syn: {Th}]