From the website:
Onna-Bugeisha, a female martial artist, are members of the samurai class. Noblewomen trained to fight for their homes, their honour and their family. These women were not ornaments; they were as dangerous as their male counterparts, amply able to defend their homes and property while the armies were away on campaign. Historically Onna-Bugeisha have been associated with the Naginata and Kaiken as fighting weapons; one very long and one very short! That is not to say they were limited to those weapons and yumi, yari, katana and teppo all feature in an Onna-Bugeisha’s armoury.