- any of the values in a series dividing the distribution of the individuals in the series into four groups of equal frequency
- any of these groups
Origin of quartileMedieval Latin quartilis ; from Classical Latin quartus, fourth: see quart
The value of the boundary at the 25th, 50th, or 75th percentiles of a frequency distribution divided into four parts, each containing a quarter of the population.
Origin of quartileMiddle English, 90 degrees apart (of the relative position of two celestial bodies), from Old French quartil, from Medieval Latin quart&imacron;lis, of a quartile, from Latin quartus, fourth; see quart.