Solon Beinfeld and Harry Bochner (editors-in-chief), Comprehensive Yiddish-English Dictionary, Indiana University Press: Bloomington and Indianapolis 2013; [also: online version with registration]
See also its Yiddish-English antecedents:
Alexander Harkavy, Yiddish-English-Hebrew Dictionary (New York 1928 and numerous photomechanical editions (intro to 1988 Yivo edition)
Uriel Weinreich, English-Yiddish Yiddish-English Dictionary (New York 1968 and photomechanical editions)
Aaron Bergman, Student’s Dictionary (edited by Itche Goldberg, New York 1968)
Yiddish-Yiddish: the four completed volumes of Yudl Mark & Judah A. Joffe, The Great Dictionary of the Yiddish Language (original prints still findable):
Note: Yudl Mark completed the set of index cards through to the end of the Yiddish alphabet. Hopefully these will all be scanned and put on line “as is” on a stable and professional website without “improvement and revision” but with a maximum of added electronic search capacity.
Thesaurus: Nahum Stutchkoff (Nokhem Stutshkov), Oytser fun der yidisher shprakh [Thesaurus of the Yiddish Language] (NY 1950). Original print edition still findable.
Yisroel Shteynberg (Israel Steinberg, with the assistance of A. Roykhverger): Hebreízmen in Yidish (Wroclaw 1949); Recommended for free download as PDF on your device and/or printout (print edition can be purchased from NYBC).
Note: Yisroel Shteynberg (1894-1970), native of Vonsove [Wąsowo], Poland (west of Poznan), poignantly dedicated his dictionary — destined to become the most important for the Semitic component in Yiddish for 21st century Yiddish students worldwide (primarily because of the thousands of full-phrase quotations from masters of modern Yiddish literature assembled over years of painstaking work) — to his father Avrom-Pinkhes, his children Zalmen and Rivke, and his Yiddish school pupils in Rutke ([Rutka], near Lomzhe [Łomża]), in Zaromb [Zareby Koscielne], in nearby Ostrov-Mazovyetsk [Ostrów Mazowiecka], and in Vasilkov ([Wasilków] near Bialystok), all of whom perished in the Holocaust. The author’s rights are asserted in Yiddish, Polish and English.
for advanced students also: