Under the proposed regulations, "for federal tax purposes... terms indicating sex, such as 'husband,' 'wife,' and 'husband and wife' should be interpreted in a neutral way to indicate same-sex spouses as well as opposite-sex spouses." This means that, under federal tax regulations, "the terms 'spouse,' 'husband,' and 'wife,' mean an individual lawfully married to another individual, and the term 'husband and wife' means two individuals lawfully married to each other. These definitions apply regardless of sex."