by callmedaddy1 May 27, 2020

by Joseph Nyamogo October 30, 2006

by LuLuBee November 8, 2010

It means act like a man, but in a non-sexist way. It is not meant to be chauvinistic or disparage other groups. Similar phrases would be "be a man," "be a mensch," "be a stand-up guy" or "wake up and accept responsibility for your actions."
Judge Marilyn Milian on THE PEOPLE'S COURT occasionally uses the term "man up" in the way described above, somewhat like an earlier TV instruction of hers to "butch up your act" but not so gay-identified. She has been provoked to the "man up" remark when confronted with such clueless men as the biological father who claimed he 'wanted to be a daddy' when he in fact had not visited his son nor contributed to his support, and the man who consistently maintained he had put only a scratch on plaintiff's car when in fact all the witnesses confirmed and all the photographic evidence showed that he had done considerable damage. It would be absurd for Judge Milian to order a woman to "man up" but she has other, analogous remarks, to make to similarly witless or hypocritical women.
by al-in-chgo February 20, 2010
