practicemakespermanent:

Boston marriage as a term is said to have been in use in New England in the decades spanning the late 19th and early 20th centuries to describe two women living together, independent of financial support from a man. The term was little known until the debut in 2000 of the David Mamet play of the same name. Since then, a trend has arisen to make mention of the term. Since 2000, many mentions of “Boston marriage” cite as examples the same few literary figures, in particular the Maine local color novelist Sarah Orne Jewett and her late life companion, the widow of the editor of The Atlantic Monthly. There is often an assumption that in the era when the term was in use, it denoted a lesbian relationship. However, there is no documentary proof that any particular “Boston marriage” included sexual relations. In general, the amount of historical and social scientific knowledge of this phenomenon, and even of the currency of the term at the turn of the 20th century, is scant.

(Courtesy of Wikipedia)