The term "wife" is most commonly applied to a woman in a union sanctioned by law (including religious law), not to a woman in an informal cohabitation relationship, which may be known as a girlfriend, partner, cohabitant, significant other, concubine, mistress etc. However, a woman in a so-called common law marriage may describe herself as a common law wife, de facto wife, or simply a wife. Those seeking to advance gender neutrality may refer to both marriage partners as "spouses", and many countries and societies are rewording their statute law by replacing "wife" and "husband" with "spouse". A former wife whose spouse is deceased is a "widow".