Definition of: Ninth

(nīnth) adjective
1. Next in order after the eighth: the ordinal of nine.
2. Being one of nine equal parts.
—noun
1. One of nine equal parts; the quotient of a unit divided by nine.
2. Music a An interval of an octave and a second, or a note separated from another by this interval. b The two notes written or sounded together.
—adverb In the ninth order, place, or rank: also, in formal discourse, ninth′ly.