Hello Cory, You could say " marimacho"

marimacho, but since women "have" same rights or it is suppossed there is no difference in what activity a woman can engage compared to men, this word is frankly in desuse. And sounds and sounded very despective.

well in Mexico marimacha and machorra are despreciatory terms to describe women who look like men as an appearance and attitud as well. if you call a girl as "marimacha" or "machorra "she gonna get mad .

http://www.thefreedictionary.com/tomboy http://www.wordreference.com/definicion/marimacho http://buscon.rae.es/draeI/SrvltConsulta?TIPO_BUS=3&LEMA=marimacho http://es.thefreedictionary.com/marimacho En el español que yo utilizo marimacho es una palabra cariñosa con la que nos dirigimos a una niña que se comporta como un chico, no tiene un tono peyorativo, generalmente, ni malsonante. No conozco otra palabra mejor para describir ese comportamiento. Ej: "No seas marimacho, te pasas el día jugando al fútbol" Machorra se utiliza despectivamente, como bollera, para referirse a las lesbianas y a las mujeres adultas con actitudes hombrunas, masculinas. Ej: "Cómo va a estar embarazada, si es machorra"

yep, i agree with cherry "marimacho" is the best way and you could also say "machona" or "machorra". although i believe they all sound like an insult, somehow more agressive than tomboy, well, at least that's how it seems to me, maybe i'm wrong.