Nikah Misyar (Arabic: المسيار) is a Nikah (marriage) carried out via the normal contractual procedure, with the specificity that the husband and wife give up several rights by their own free will, such as living together, equal division of nights between wives in cases of polygamy, the wife's rights to housing, and maintenance money ("nafaqa"), and the husband's right of homekeeping, and access etc.
Essentially the couple continue to live separately from each other, as before their contract, and see each other to fulfil their needs in a permissible (halaal) manner when they please.
Sheikh Ahmed al-Kubaissi from the United Arab Emirates thinks there is no formal problem with 'misyar' marriage. It fulfils all the demands of Islamic law. Nevertheless, he describes it as contrary to the norms of decent Islamic life.
Read more about Nikah Misyar: Background and Causes, Misyar Marriage in Practice, Legality of Misyar Marriage, Criticism of Misyar