very interesting, thank you. I think in this case its eastern Ashkenazic derived meaning ‘tobacco seller’. This is what I always heard.
This two apps come to mind as far as learning the basic vocabulary is concerned.
Beginner Yiddish https://play.google.com/store/apps/details?id=com.shex.beginneryiddish
StartFromZero_Yiddish https://play.google.com/store/apps/details?id=com.shex.startfromzero_yiddish
The Easy-Shmeezy Guide to Yiddish by Moshe Sherizen contains 1500 most common Yiddish words. I bought it when it first came out in digital form. It's a good book.
On Amazon it had amazing reviews. Old copies there are off the charts price-wise. But the EU has newer copies for sale that are much more reasonable.
Take a look: https://smile.amazon.com/Intensive-Yiddish/dp/1897744072/ref=sr\_1\_1?crid=1OVQ946YANT6H&keywords=Intensive+yiddish&qid=1668992015&sprefix=intensive+yiddish%2Caps%2C86&sr=8-1#customerReviews
There are plenty of books on and in Yiddish!
That said, there are books with transliterated Yiddish, but I don’t have much experience with them. Like this? https://www.amazon.com/Yiddish-Dictionary-Sourcebook-Transliterated-Language/dp/0870687158
Possibly a euphemism turned into an insult? "Optret", to use YIVO transliteration, means a retreat or going away somewhere (compare German "Abtritt"). In Yiddish (and, apparently, in older German slang) this can take on the meaning of "toilet". I think dict.cc's translation of the German "Abtritt" in that euphemism sense choose a more accurate word in English: "privy", with the sense of seeking privacy.
What context did your grandmother say it was used in? Like "you optret!" or "It smells like an optret in here!" Or something else?
For reference, Refoyl Finkel's Online dictionary and dict.cc's entry on "Abtritt".
Hallo! Haben Sie dieses Buch versucht?
https://www.amazon.de/Lehrbuch-modernen-jiddischen-ausgew%C3%A4hlten-Lesest%C3%BCcken/dp/3871189871
Die Kundenrezensionen sind gut (Amazon UK, US und DE). Es gibt ein paar mehr Bücher, aber habe ich keine Deutschsprachige Lehrbücher benutzt.
Du kenst es bakumen af amazon (azoy vi di frierdike numern)!
I can see you've gotten help already, but if it's of any interest there's a great anthology of Yiddish folktales by Beatrice Weinreich which I love!
I'll attach an Amazon link if you want to look into it: https://www.amazon.com/Yiddish-Folktales-Pantheon-Folklore-Library/dp/0805210903
I really enjoyed this one. It's nonfiction, it's the memoir of a guy who was born into a rich family in Galicia in the mid 19th C and later emigrated to the US and became a journalist. He remembers every detail of life in the 1860s-70s and still holds grudges about people when he was writing his memoir in Yiddish half a century later.
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https://www.amazon.ca/World-Apart-Memoir-Nineteenth-century-Galicia/dp/1934843636
Just to share, the free Beginner Yiddish app is a daily flashcard tool that is pretty efficient in building up your Yiddish vocabulary from scratch.
College Yiddish from Weinreich is still the most-used Yiddish textbook. Rebecca Margolis' Basic Yiddish is also excellent (there is also an online version that I can access through my university, maybe yours too!).
I have never even heard of Colloquial Yiddish or Assimil Yiddish so I can't comment on them.
Also, be aware that Yiddish orthography (spelling) varies between dialects, so if you're going to primarily be working on Russian and Polish Yiddish literature, spend some time researching the different orthography systems. It will save you a lot of headache.