The word steak is basically the same word as stake . Both come from the same root as the word stick , except that steak came by way of the language of the Vikings who conquered northern England. In Old Norse, steikja meant a piece of meat roasted on a stake, or stick--that is, on a rotating spit. As early as the 14th Century, English cookbooks were referring to "stekes of venisoun or beef."
Probably it was a reasonably big piece of meat on that spit, and the steaks were sliced off it. That would explain how a steak came to be a cut sliced crosswise to the grain of the meat (for tenderness). In any case, the Norse steikja had a profound effect on English butchering practice. While in France and most other European nations, the main idea of butchering meat is separating the various muscles (such as the filet), English-style butchering has long occupied itself with slicing through the muscles to get steaks and chops.
We think of steak as a substantial meal today, but 200 years ago, it was considered no more than a quick snack, and you'd have apologized if you served a steak dinner. A "joint," now--a whole roast, that is--that was a real meal.