Definition of quintile in US English:



  • 1Statistics
    Any of five equal groups into which a population can be divided according to the distribution of values of a particular variable.

    • ‘The low level of wealth in at least the bottom two quintiles of the income distribution suggests that substantial numbers of people are likely to face such constraints.’
    • ‘In 1980, a majority of voters in three out of five income quintiles reported choosing the Democratic candidate, and the fourth quintile was nearly tied.’
    • ‘The study grouped doctors into five quintiles by number of procedures a year: 1 to 33, 34 to 89, 90 to 139, 140 to 206 and 207 to 582.’
    • ‘For example, leftists point to studies showing that the gap between the bottom quintile and the top two quintiles is increasing.’
    • ‘All statistical models were consistent with this finding except for one, which categorized patients by quintile and showed no mortality difference in the first quintile.’
    1. 1.1 Each of the four values of the random variable that divide a population into five groups.
      • ‘As the NSW hospitals data had also been geo-coded, we could impute an EFI quintile for each patient, based on the actual distribution of SES at the Collection District-sex-age level.’
      • ‘The terms tercile, quartile, quintile and decile should refer to the percentiles which divide the distribution into 3, 4, 5, or 10 equal parts, respectively.’
      • ‘They analyzed baseline serum vitamin A concentration in relation to risk for hip fractures as a continuous variable and by quintiles.’
      • ‘Socioeconomic status was measured by the equivalent family income quintile of the patient.’
  • 2Astrology
    An aspect of 72° (one fifth of a circle).

    • ‘As it has then gone three fifths around the zodiac or 216°, that is three quintile divisions, in the other direction, it is again pointing towards Earth, and this is within less than one degree!’
    • ‘That quintile between Pluto and Uranus met and re-met altogether five times (due to the retrograde motions), and Plutonium was created at the last of these five quintiles.’
    • ‘The quintile refers to knowing and the empowerment which comes from knowing.’


Early 17th century: from Latin quintilis (mensis) ‘fifth month, July’, from quintus ‘fifth’.