We would like to quote Dr. Rif`at Fawzi, professor of Shari`ah at Cairo University, who stated:

As for removing the hair from between the eyebrows, it is lawful, because it is not part of the eyebrows. But as for plucking the eyebrows, it is forbidden and not permissible in Islam, according to the Hadith: ‘May Allah’s curse be inflicted upon women who pluck their eyebrows, and women hired to do this.’
What is prohibited is an-Nams, which denotes removing the hair of the eyebrows by plucking in order to make it thin. The Prophet (peace and blessings be upon him) is reported to have cursed both women who do the plucking and those who seek to have it done. (Reported by Abu Dawud)”.