Formal:
* ווילקאָמען (vilkomn) - This is the most common and formal way to say "welcome." It's equivalent to "welcome" in English.
Informal:
* אַ גוטן טאָג (a gutn tog) - This literally means "a good day" and is used as a greeting similar to "welcome" in English.
* זיי גוט (zay gut) - This means "be well" and can be used as a friendly greeting, similar to "welcome" in informal settings.
Other options:
* ברוך הבא (broch haba) - This is a Hebrew phrase that means "welcome" and is sometimes used in Yiddish.
* אַ שיין טאָג (a shayn tog) - This means "a beautiful day" and can be used as a more poetic greeting.
The best way to say "welcome" in Yiddish depends on the situation and your relationship with the person you are greeting.