מעיין זײַן

Could you please add homonimous form «מעיין» with variant «מעין» with meaning «spring, well» (קוואל). It is included in Yiddish dictionaries of Hebraisms, e.g. that of Pereferkovich (1929, page 173), although without transcription, or Yehoshua (1927, page 165).
The word is used, for example, in Avrom Rechtman's book about Jewish ethnography (יידישע עטנאגראפיע און פאלקלאר, ז.271) within description of Chasidic singing traditions: «מעין נגינה».