All of these are the first definitions found for the respective word on Urbandictionary.com

Men:

"Things With Penises who tell women anything just to get intercorse"

Women:

"Beings not seen or touched by 98% of the men who have posted on this subject thus far. Highly attracted to males of the species who are reasonable to look at, have jobs, are relatively kind, sometimes take out trash, and treat them like equals (not superiors, not inferiors -- equals.) Happily give blowjobs in return. Prefer large dicks. Secretly laugh at guys who convince themselves that size doesn't matter. Are paid seventy five cents for every dollar a man makes in the exact same job, same demographic, and same education level. To those men who cannot procure them (because said men are too mean, stupid, sexist, ugly, and unaccomplished) they cause intense feelings of failure, hatred, prejudice, violence, and need to post on boards stereotyping all women with one narrow, negative definition. Said men then jack off alone. When said beings reject such specimens of men or express an intelligent opinion, they are bitches. When they don't put out, they are also bitches. When they do, they are sluts."

Man:

"Someone who is obsessed with women making them sandwiches."

(no definition for woman)

Boys:

"an animal that can talk"

Girl:

"A younger form of a woman. If you tried to have sex with a girl, you'd be arrested, you damn pedophile."

Male:

"something gifted with two heads, but only uses one or the other...or neither"

female:

"Most definately the finest thing ever created"

MRA:

"MRA" means "men's rights activist."

An MRA is a white man who insists against all evidence and decency that white men are oppressed and than women and minorities are "revered and privileged."

An MRA would never support the rights of those men who truly are at a disadvantage in our society: homosexual and black men. Instead, he leaves campaigning for LGBT rights and minorities' rights to the "evil evil cunt bull dykes" aka feminists.

An MRA sits on a huge pile of white and male privilege and keeps whining that he is oppressed."

Mens Rights Activist:

"A men's right activist is a man (sometimes a brainwashed female supporter) who delusionally believes that despite global patriarchy men are somehow oppressed. Similar to middle class white dudes whining about "reverse racism". The power dynamics that exist in society and have for a very long time mean that men are the class that holds the power. They are the oppressor class so when bad things happen it is not sexism because men do not face discrimination, terrorism and forced impregnation based on their sex. Like's to claim "misandry" as if it were equal to misogyny. They don't seem to realize a misandrist is actually someone who is misanthropic."

Feminist:

"someone who believes the radical notion that women are people."

Misandry:

Generally, "misandry" refers to the hatred and oppression of men on a genotypic basis.

As sociologist Allan Johnson notes, "misandry" has no place in a male-identified, male-centered world. Moreover, Johnson states: “And it takes almost no criticism at all in order for men to feel "bashed," like it's "open season on men." In fact, just saying "male privilege" or "patriarchy" can start eyes rolling and evoke that exasperated sense of "Here we go again.” (Allan Johnson, “Privilege, power and difference,” p. 197) "Accusations of male bashing and man hating work to discredit feminism because people often confuse men as individuals with men as a dominant and privileged category of people. Given the reality of women's oppression, male privilege, and some men's enforcement of both, it's hardly surprising that EVERY woman should have moments when she resents or even "hates" men.” (Allan Johnson, "The gender knot," p. 107 “Both movements (white supremacists and male supremacists) attack women and people of color for playing the victim card because they see white men as the real victims. (Michael Kimmel, "Privilege: A reader," p. 325)

Misogyny:

"The hatred of women."