Feminine gender specific term synonymous with "man up" meaning do the thing, take care of your stuff, be your own grown up.
Hon, need you to fem up - please fix the transmission and start the casserole.
by msdee January 06, 2017
when a female goes to the bathroom during menstruation to apply/insert feminine hygeine products (tampons/sanitary napkins).
"I'm just going to fem-up"......
by melsi lee October 17, 2006