Shaykh Ibn ‘Uthaymeen (may Allaah have mercy on him) said: “If removing hair from the eyebrows is done by plucking, this is namas (plucking the eyebrows) and the Prophet (saws) cursed the naamisah (the woman who plucks eyebrows) and the mutanammisah (the woman who has her eyebrows plucked). This is a major sin, and women are singled out in this ruling because they are the ones who usually do this, for the purpose of beautification, but if a man were to do it he would also be cursed, just as a woman is cursed for doing this, Allaah forbid.
If hair is removed from the eyebrows by a method other than plucking, such as by cutting or shaving, some of the scholars regard this as being the same as plucking, because it is changing the creation of Allaah, so there is no difference between plucking, cutting or shaving. This is undoubtedly more on the safe side, so a person must avoid that, whether man or woman.”