Yiddish, Yiddishkeit (c.G.),
Jewish, Judaism.

Yigdal (H.),
hymn summarizing the thirteen creeds drawn up by Maimonides.

Yom Kippur (H.),
Day of Atonement.

Yom tof (H.), lit.,
good day; Festival.

Yontovdik (hybrid H.),
pertaining to the Festival.

Yosher-Kowach (c.H.),
May your strength increase! = Thank you; a formula to express
gratitude—especially at the end of a reading.