The Hebrew calendar follows a seven-day weekly cycle.

The names for the days of the week are simply the day number within the week.

In Hebrew, these names may be abbreviated using the numerical value of the Hebrew letters,

for example יום א׳ (Day 1, or Yom Rishon (יום ראשון)):

Yom Rishon – יום ראשון (abbreviated יום א׳) = “first day” = Sunday (starting at preceding sunset or evening on Saturday).
Yom Sheni – יום שני (abbr. יום ב׳) = “second day” = Monday (starting evening time on Sunday).
Yom Shlishi – יום שלישי (abbr. יום ג׳) = “third day” = Tuesday (starting evening time on monday).
Yom Reviʻi – יום רביעי (abbr. יום ד׳) = “fourth day” = Wednesday (starting evening time on Tuesday).


Yom Chamishi – יום חמישי (abbr. יום ה׳) = “fifth day” = Thursday (starting evening time wensday).
Yom Shishi – יום ששי (abbr. יום ו׳) = “sixth day” = Friday (starting evening time on thursday).
Yom Shabbat – יום שבת (abbr. יום ש׳) or more usually שבת – Shabbat = “Sabbath day (Rest day)” = Saturday (starting evening time on friday 18 minutes before the sun goes down)

The names of the days of the week are modeled on the seven days mentioned in the Creation story. For example, Genesis 1:5 “… So the evening and morning, were the first day (one day”). One day also translates to first day or day one.
In Hebrew, the word Shabbat (שַׁבָּת) can also mean “(Talmudic) week”.