] This post doesn't seem to have anything explicit about Jane Austen and her works. [etc.]

Since I don't hang out here, I didn't realize the board was so specific. I just thought that if in Jane's time, "cavalry" definitely meant horses, and it doesn't now, one of the regulars here might know how the term had evolved to the present day...

I see Stephanie has answered so that's all I needed, thanks! =)