Being aggressively disrespectful of women who support women's rights. Male students may interrupt women frequently, often with personal or irrelevant remarks. They may ridicule women when they do speak, thus discouraging or intimidating them from participating. Men may simply frown or groan when some women speak in class, especially if the women are very bright or assertive. Some women are fearful of raising women's issues in class because of the hostility they may face from male students.
Men also harass other men, for example, gay men.
Many of the examples in this web page are also applicable to these situations. Joking is a time-honored way to mask hostility. Many jokes told about women cast women in a poor light or degrade them. Thus, the person being harassed, rather than the harasser, is made to feel at fault. Jokes about rape are not uncommon.