"yais" can't be defined conventionally. one would be less successful at defining "yais" than he/she would be at defining the contemporary english language's utility infielder, "like". "yais" is a state of mind. "yais" is understanding and misunderstanding, as well as all points described on the subsequent continuum.
you are lovely, yais; gay, yais; yais? yais; is two plus two, four? yais; (if i had the character spaces to continue, i probably wouldn't. yais.)
Slang term for xylophone, a tuned melodic percussion instrument, made of either wood, kelon, or a similar resonant material. Often having a musical range of at least two octaves, xylophones have a very articulate and characteristic sound. They are a very important instrument in today's bands and orchestras.
OK percussion, sort out the parts, and make sure you remember there is a xylophone solo during this piece.
Did you guys hear that wicked xylophone solo in Sabre Dance?