Sat·ur·day 
(sătər-dē, -dā′)
(sătər-dē, -dā′)n.
Abbr. Sat. or S The day of the week that comes after Friday and before Sunday.
[Middle English, from Old English Sæternesdæg, translation of Latin Sāturnī diēs : Sāturnī, genitive of Sāturnus, Saturn + diēs, day.]
Satur·days adv.