\Six"teenth`\, a. [From {Sixteen}: cf. AS.
sixte['o]?a.]
1. Sixth after the tenth; next in order after the fifteenth.
2. Constituting or being one of sixteen equal parts into
   which anything is divided.
{Sixteenth note} (Mus.), the sixteenth part of a whole note;
   a semiquaver.

\Six"teenth`\, n.
1. The quotient of a unit divided by sixteen; one of sixteen
   equal parts of one whole.
2. The next in order after the fifteenth; the sixth after the
   tenth.
3. (Mus.) An interval comprising two octaves and a second.
   --Moore (Encyc. of Music.)