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quantile vs. percentile

quantile

[kwon-tahyl, -til] / ˈkwɒn taɪl, -tɪl /

noun

Statistics.

one of the class of values of a variate that divides the total frequency of a sample or population into a given number of equal proportions.

percentile

[per-sen-tahyl, -til] / pərˈsɛn taɪl, -tɪl /

noun

one of the values of a variable that divides the distribution of the variable into 100 groups having equal frequencies.

Ninety percent of the values lie at or below the ninetieth percentile, ten percent above it.

adjective

of or relating to a percentile or a division of a distribution by percentiles.