Source : Webster's Revised Unabridged Dictionary (1913)

Saturday \Sat"ur*day\ (?; 48), n. [OE. Saterday, AS.
   S[ae]terd[ae]g, S[ae]ternd[ae]g, S[ae]ternesd[ae]g,
   literally, Saturn's day, fr. L. Saturnus Saturn + AS. d[ae]g
   day; cf. L. dies Saturni.]
   The seventh or last day of the week; the day following Friday
   and preceding Sunday.

Source : WordNet®

Saturday
     n : the seventh and last day of the week; observed as the
         Sabbath by Jews and some Christians [syn: {Sabbatum}, {Sat}]