ahavas yisrael	(lit., the love of Israel): the love for one's fellow Jews
achdus Yisrael	(lit., the unity of Israel)
Amalek	The first nation to attack the Jewish people after the exodus from Egypt (Shmos, ch. 17); subsequently, as well, the arch-enemy of our people
Asiyah, the World of	(lit., "the World of Action, or Making"): the lowest of the four spiritual worlds, the realm of spiritual existence which relates directly to our material world
atik, atik yomin	(lit., "ancient days"): an elevated spiritual level that is in absolute oneness with G-d's essence
Atzilus, the World of	(lit., "the World of Emanation"): the highest of the four spiritual worlds
baal teshuvah	(lit. "master of return"; pl. baalei teshuvah): a person who turns to G-d in repentance
Beis HaMikdash	The Temple in Jerusalem
Beraisa, pl. beraisos	A body of teachings authored during the same period as the *Mishnah, but not included in that text; when not capitalized, the term refers to a single teaching of this type
Beriah, the World of	(lit., "the World of Creation"): the second (in descending order) of the four spiritual worlds
Binah	(lit., "understanding"): the second of the Ten *Sefiros, or divine emanations; the second stage of the intellectual process, the power that develops abstract conception, giving it breadth and depth
bittul	self-nullification, a commitment to G-d and divine service that transcends self-concern
chassid	a pious, kind-hearted person, whose commitment extends beyond the requirement of the law
chinuch	education
Eretz Yisrael	(lit., the land of Israel)
Gan Eden	(lit., the Garden of Eden): the place in which the narrative of Adam and Eve occurred, borrowed to refer to the spiritual realm of souls in the afterlife
Gemara	one of the portions of the Talmud; the elucidation of the Mishnah, and the discussion of related concepts by the Sages
halachah	the body of Jewish Law; alternatively a single law
Kabbalah	(lit., "received tradition"): the Jewish mystical tradition
kabbalas ol	(lit., "the acceptance of [G-d's] yoke"): an unswerving, selfless commitment to carrying out the will of G-d
Lashon HaKodesh	(lit., "the Holy Tongue"): Biblical Hebrew
Mashiach	the Messiah
mashpia	(lit., "source of influence"): one who plays an active role in the spiritual development of a person or his environment
Men of the Great Assembly	The body of 120 Sages convened by Ezra at the beginning of the Second Temple Era which canonized the Bible, structured the prayer service, and presided over the renewal of Jewish practice in Eretz Yisrael after the return from the Babylonian exile
mezuzah (pl., mezuzos)	the parchment scroll affixed to the doorpost, and containing the first two paragraphs of Shema (Devarim 6:-9 and 11:13-21)
Midrash	the classical collection of the Sages' homiletical teachings on the Bible
mikveh	a ritual bath
mili dechassidusa	pious conduct beyond the measure of the law
Mishlei	The Book of Proverbs
Mishnah	the first compilation of the Oral Law authored by Rabbi Yehudah HaNasi (approx. 150 C.E.); the germinal statements of law elucidated by the Gemara, together with which they constitute the Talmud; when not capitalized, a single statement of law from this work
mitzvah	(lit., "commandment; pl., mitzvos): one of the 613 Commandments; in a larger sense, any religious obligation
Nasi	(a) in Talmudic times, the head of the Sanhedrin, the highest Jewish court; (b) in later generations, the civil and/or spiritual head of the Jewish community at large
Pirkei Avos	The Ethics of Our Fathers; the Talmudic tractate which focuses on ethics
pnimiyus HaTorah	(lit., "the inner dimension of [the Torah]"): the mystical dimension of Torah study
pushkah	charity box
Rebbe	(lit., "my teacher [or master]"): saintly Torah leader who serves as spiritual guide to a following of chassidim
sefirah, pl. Sefiros	the Kabbalistic term for the attributes of G-dliness which serve as a medium between His infinite light and our limited framework of reference
Shabbos	the Sabbath
Shema	the fundamental Jewish prayer which we are obligated to recite each day, in the evening and in the morning
siddur	a prayer book
Talmud	the basic compendium of Jewish law, thought, and Biblical commentary, comprising *Mishnah and *Gemara; when unspecified refers to the Talmud Bavli, the edition developed in Babylonia, and edited at end of the fifth century C.E.; the Talmud Yerushalmi is the edition compiled in *Eretz Yisrael at end of the fourth century C.E.
Tanach	The Bible
Tanya	the classic text of Chabad chassidic thought authored by the Alter Rebbe
tefillin	small, black leather boxes each containing four Biblical passages which the Torah commands adult males to wear daily
teshuvah	(lit., "return [to G-d]"): repentance
tzaddik	righteous man
tzedakah	charity
World to Come	a) the afterlife; b) the Era of the Resurrection of the Dead
yetzer hora	the evil inclination
Yetzirah, the World of	(lit., "the World of Formation"): the third (in descending order) of the four spiritual worlds
yiras shomayim	the fear of Heaven
Zohar	(lit., "radiance"): the title of the classic mystical work embodying the teachings of the *Kabbalah