quin•tilePronunciation: (kwin'til, -tīl), [key]
a quantile for the special case of five equal proportions.
a quintile aspect.
of or pertaining to the aspect of two heavenly bodies that are one fifth of the zodiac, or 72°, apart.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.