Saturday 

Saturday is the day of the week named after the planet Saturn.

Even though the name reeks of being associated with Sun Worship, and the worship of other heavenly bodies, this term is used by members of most, if not all, major Religions.

Some consider Saturday to be the last day of the Week and some consider it to be the first Day of the Week.  What Day if the Week it is considered to be is not really very important. It is simply the name of one of the Days of the Week.

The Jewish week starts on Saturday as Saturn is or was considered to be the Planet of Yahweh. (See MPD_0032)