"Wife" refers to the institutionalized relation "to the other spouse", unlike mother, a term that puts a woman into the context of her children. In some societies, especially historically, a "concubine" was a woman who was in an ongoing, usually matrimonially oriented relationship with a man who could not be married to her, often because of a difference in social status. 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". The status of a wife may be terminated by divorce, annulment, or the death of a spouse. In the case of divorce, terminology such as "former-wife" or "ex-wife" is often used. With regard to annulment, such terms are not, strictly speaking, correct, because annulment, unlike divorce, is usually retroactive, meaning that an annulled marriage is considered to be invalid from the beginning almost as if it had never taken place. In the case of the death of the other spouse, the term used is widow. The social status of such women varies by culture, but in some places, they may be subject to potentially harmful practices, such as widow inheritance or levirate marriage; or divorced women may be socially stigmatized. In some cultures, the termination of the status of wife made life itself meaningless, as in the case of those cultures that practiced sati, a funeral ritual within some Asian communities, in which a recently widowed woman committed suicide by fire, typically on the husband's funeral pyre. The legal rights of a wife have been since the 19th century, and still are, in many jurisdictions subject to debate. This subject was in particular addressed by John Stuart Mill, in "The Subjection of Women" (1869). Historically, many societies have given sets of rights and obligations to husbands that have been very different from the sets of rights and obligations given to wives.