fif•teenthPronunciation: (fif'tēnth'), [key]
next after the fourteenth; being the ordinal number for 15.
being one of 15 equal parts.
a fifteenth part, esp. of one (1/15
the fifteenth member of a series.
the interval of two octaves.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.