Dancing is not haram for women in principle, and no prohibition on that has been narrated from the Prophet (blessings and peace of Allah be upon him). Rather it was narrated from the Prophet (blessings and peace of Allah be upon him) that he saw an Ethiopian woman dancing, and he let `Aa’ishah watch her, and did not tell her not to watch.
Whether the hadith about the Ethiopian woman dancing is authentic or not, the juristic principle that things are permissible unless there is evidence to the contrary supports the view that dancing is permissible.
But dancing is almost always accompanied by music and singing, provocation of desire, and going to extremes in making enticing movements. The matter has become even worse in modern times, when people have begun to imitate indecent western dances that promote immorality.
Imported dance styles wearing revealing clothing have become widespread, there is a great deal of free mixing and the temptation has become greater, and skill is measured by how much the dance resembles that of disbelievers, infamous evildoers and immoral women. Therefore all the scholars have declared this to be prohibited, so as to bar the means that can lead to this evil.