Shovavim

The term shovavim is a Hebrew acronym consisting of the initial letters of the parshioth (Torah portions) of "Shemot", "Va'era", "Bo", "B'Shallach", "Yitro" and "Mishpatim".

During a Jewish leap-year, this period is extended to an eight-week sequence called "Shovavim Tat", derived by adding the next two portions, "Terumah" and "Tetzaveh", to the list.

[3] The custom of fasting in a leap year is also mentioned in Sefer Haminhagim of Isaac Tyrnau.

Some have the customs of studying laws relating to such transgressions, fasting and giving extra tzedakah (charity) during this time, and of reciting Selichot and other tikkunim (Kabbalistic prayers or meditations) designed to counteract their harmful effects.

Since these customs were popularized by Jewish Kabbalistic teachings, Sephardic and Hassidic Jews are more likely to follow them than their Ashkenazic counterparts.

[6] A special type of fast called a ta'anit dibbur is observed by some during the Shovavim period.

During the entire day (usually Shabbat, when regular fasting is prohibited), between sunrise and dusk, one refrains from superfluous speech.