\Sixth\, a. [From Six: cf. AS. sixta, siexta.]
1. First after the fifth; next in order after the fifth.
2. Constituting or being one of six equal parts into which
   anything is divided.

\Sixth\, n.
1. The quotient of a unit divided by six; one of six equal
   parts which form a whole.
2. The next in order after the fifth.
3. (Mus.) The interval embracing six diatonic degrees of the
   scale.