Definition from Wiktionary, the free dictionary
quintile (plural quintiles)
- (statistics) Any of the quantiles which divide an ordered sample population into five equally numerous subsets.
- (by extension) A subset thus obtained.
- (astrology) An aspect of planets that are distant from each other by one fifth of a zodiac (72°)
- (statistics): median (2-quantile), tercile/tertile (3), quartile (4), quintile (5), sextile (6), septile (7), octile (8), decile (10), hexadecile (16), ventile/vigintile (20), centile/percentile (100)