The food has come to English through various cultures and languages, and may be spelled according to its cultural context or linguistic source: varenyky in a Ukrainian context, vareniki in a Russian or Jewish context, or wareniki or wareneki in a Mennonite context.
The name of the dish is often treated as plural only, but the singular form varenyk or varenik is in use. Sometimes back-formed plurals like varenikes, varenikis, or varenykys also appear occasionally.
From Ukrainian варе́ники plural (varényky), singular варе́ник (varényk). Also borrowed from Russian варе́ники (varéniki), Plautdietsch wareniki, and others. The Ukrainian term descends from ва́рений (várenyj, “boiled”), from вари́ти (varýty, “to boil, to cook”), from Old East Slavic варити (variti), from Proto-Slavic *variti (“to cook”) + masculine ending -ик (-yk). Compare вар (var, “boiling liquid; cooking, boiling”), from Proto-Slavic *varъ, from Proto-Indo-European *wer- (“to burn, blacken”).