A B D E F G H I K Ch L M N O P R S Sh T Tz U V Y Z

Ladino The colloquial language of Sephardic Jews, based primarily on Spanish, with words taken from Hebrew, Arabic and other languages; and written in the Hebrew alphabet
Lag B'Omer Approximately halfway between Pesach and Shavuot during the counting of the Omer. It is recognized as the time in which the Hadrianic persecutions somehow ceased; there were celebrations in the shtetl surrounding recognition of Bar Kochva's heroism; and it was the day of death of Rabbi Simon bar Yohai. It is considered a scholar's holiday, today celebrated by school picnics and weddings (since they are prohibited during the omer period); it is alternately referred to as Lag L'Omer by Sefardim
Lamed - L Twelfth letter of the Hebrew alphabet
Lamed-vavniks (Yiddish) One of the 36 According to one legend, the fate of the human race rests on the shoulders of the 36 truly righteous ones of each generation. Those who are of that select group are thus designated by the Hebrew letters for the number 36, lamed-vav, and colloquially called "lamed-vavniks"
Lapidut Torch; One who brings forth light Also a term for the Mashiach
Lashon Harah Evil tongue Encompasses all forms of forbidden speech (gossip, slander, lying, etc.).  According to the Talmud, slander is a hideous capital crime; a slanderer is like one who denies G-d; G-d says of the slanderer: "He and I cannot live together in the world" (Arachin 15b)
Lashon Kodesh (al. Leshon HaKodesh) The 'Holy Tongue' The Mishnah refers to the Hebrew language as leshon ha-kodesh, the holy tongue, to distinguish it from the Aramaic vernacular or other "secular languages" spoken by the Jewish people (Sotah 7:2-4; 8:1).

According to RaMBaM, the reason for calling Hebrew leshon ha-kodesh  lies inthe fact that it falls short of indecent expressions and "has no special name for the organ of generation... nor for the act of generation itself... It only describes them in figurative language and by way of hints, as if to indicate thereby that these things should not be mentioned, and should therefore have no names; we ought to be silent about them, and when we are compelled to mention them, we must manage to employ for that purpose some suitable expressions, although these are generally used in a different sense..." (Guide 3:8).

Others have affirmed that Hebrew is G-d's language, in which He gave us the Torah.  It was the Hebrew language in which the prophets expressed their lofty ideas and our fathers breathed forth their sufferings and joys.  One cannot understand the people of Yisrael without understanding Hebrew

Latkes Potato pancakes, also called levivot, part of the Chanukkah celebration because they are fried in oil
Lebun A process using heat (or blowtorch) in order to make a certain set of utensils kosher for Pesach
Lechah Dodi Come My Beloved A mystical prayer that speaks of the Shabbat (as) Bride, sung on Friday evening to welcome Shabbat
L'Chaim To Life Used as a toast
Lechu Neranenah Come, Let Us Sing Tehillim 95 begins with the words "come, let us sing" and is the first of the six psalms that introduce the Shabbat-eve service.  Together with the hymn welcoming the Shabbat bride (Lechah Dodi), they form what is termed Kabbalat Shabbat, the serviced immediately preceding the Maariv on Friday evenings. 

The six psalms, selected by the Kabbalists of the 16th century in Eretz Yisrael, are said to symbolize the six workdays of the week.  The seventh psalm follows Lechah Dodi, since it is "a song for the Shabbat day" (Tehillim 92)

The reason given for the selection of Tehillim 95-99 and 29 is that the initial letters of these six hymns, in the Hebrew text, have the numerical value of 430, equaling that of the word nefesh (soul). 

Furthermore, Tehillim 29 contains the Divine Name 18 times, corresponding to the 18 benedictions fo the Shemoneh Esrei prayer, and the 18 times G-d is mentioned in the Shema.  Tehillim 29 ends with an assurance of G-d's favor to his people

Leshanah HaBa'ah Next Year in Yerushalayim Liturgically used twice a year: at the end of the Seder service and at the end of the Neilah service.  This custom is explained on the basis of the well-known difference of opinion that prevailed between the Tannaitic Sages Rabbi Eliezer and Rabbi Joshua.  According to one, the future deliverance of Yisrael will take place during Nisan just as they were liberated from Egyptian slavery during Nisan; according to the other the future deliverance will occur during Tishri
L'Shanah Tovah Tikateiv V'Tichatem May you be inscribed and sealed (in the Book of Life) for a good year
Levayat HaMet The mitzvah of accompanying the dead to the grave, by way of funeral and interment
Levi (pl. Leviim) Levite A descendant of Levi, the son of Yaakov (excluding the priestly descendants of Aharon), whose role was to assist the Kohen in the Temple
Levush (pl. Levushim) Garment
Lifnim Mi-Shurat HaDin Higher Moral Law (literally: "inside the line of the law" but interpreted in the sense of "beyond the line of the law") Refers to a man's duty not to insist on the legal rights accorded to him in a lawsuit, such as compensation and damages, but to renounce them in favor of his litigant who happens to be economically weak.   If the matter in dispute is a question of money between a rich man and a poor man, the judge is not to give a wrongful verdict in favor of the poor man out of antipathy to the rich and powerful.  Sympathy and compassion are great virtues, but even these feelings must be silenced in the presence of justice
Lishmah   The 6th chapter of Pirkei Avot (Ethics of the Fathers) that begins with the statement that whoever engages in Torah for its own sake merits many thins; nay more, the whole world is worthwhile for his sake.  He is described as a beloved friend, who loves G-d and mankind; he pleases G-d and mankind.  The Torah invests him with humility and respect.  Men are benefited by his counsel and sound wisdom, by his understanding and strength.

RaMBaM, in his Mishnah Commentary, points out:

Since man is accustomed to act according to the good or the harm which may result, he loses nothing by shaping his conduct with a view to reward and punishment until, by habit and zeal, he arrives  at an understanding of the truth and serves purely out of love.  The human spirit is narrow and, while acquiring wisdom, hopes for other, more material advantages.  In searching for truth, the goal is truth itself.

Livyatan The name of an archetypal sea-creature, which is destined to wage battle against the Behemot to only be consumed by the righteous at the end of days
Luach Calendar Specifically referring to either the months of the year, when holidays occur, and which Torah portions are to be read on which week
Lulav (pl. Lulavim) Palm Branch On of the four species taken up and ritually shaken on the Festival of Sukkot (Booths). It is bound up with two other species--the hadat (myrtle branch) and the aravah (willow branch) and held together with the etrog during the performance of this ritual. These altogether are referred to as the Lulavim