Gyros, pronounced yee-ros (with a rolled R, IIRC). I believe that gyros is the singular term, but there is disagreement on this front.

All the gyros I've ever eaten contained shaved lamb meat (they shaved the cooked meat of the lamb, rather than the wool off the lamb... well, they probably did that before they killed the lamb... anyway), various condiments, and cucumber sauce. Scrum-diddly-umptious.