Webster's Revised Unabridged Dictionary · 1913

Eleventh

Eleventh , adjective

[Compare Anglo-Saxon endlyfta. See Eleven.]

1.
Next after the tenth; as, the eleventh chapter.
2.
Constituting one of eleven parts into which a thing is divided; as, the eleventh part of a thing.
3.
(Music) Of or pertaining to the interval of the octave and the fourth.

Eleventh , noun

1.
The quotient of a unit divided by eleven; one of eleven equal parts.
2.
(Music) The interval consisting of ten conjunct degrees; the interval made up of an octave and a fourth.