sistern

From Middle English sisterne, systerne, sistren, sustren, sustern, equivalent to sister +‎ -en; or alternatively modelled after brethren.

sistern

1. (nonstandard) Alternative form of sistren
   • 1896, Ernest Emory Russell, The Reason why: A Story of Fact and Fiction, page 29:

     But, my dear brothern an' sistern, they hain't no water down thar— it's a awful thing to think they hain't, but they hain't, b'caze the Bible says they hain't.

• cistern

• Inserts, Stiners, Strines, estrins, inserts, sestrin, sinters, sistren