1. [n]  a ninth part
2. [n]  position nine in a countable series of things; "going into the ninth they were a run ahead"
3. [adj]  coming next after the eighth and just before the tenth in position

NINTH is a 5 letter word that starts with N.

1. \Ninth\, a. [From {Nine}; cf. AS. nigo[eth]a.]
   1. Following the eight and preceding the tenth; coming after
      eight others.
   
   2. Constituting or being one of nine equal parts into which
      anything is divided.
   
   

2. \Ninth\, n.
   1. The quotient of one divided by nine; one of nine equal
      parts of a thing; the next after the eighth.
   
   2. (Mus.)
      (a) An interval containing an octave and a second.
      (b) A chord of the dominant seventh with the ninth added.