quartile

UK: /ˈkwɔːtaɪl/ US: (kwôr′tīl, -til)

WordReference Random House Unabridged Dictionary of American English © 2025

quar•tile  (kwôr′tīl, -til), n. 

1. Statistics (in a frequency distribution) one of the values of a variable that divides the distribution of the variable into four groups having equal frequencies. Cf. first quartile, median, third quartile. 
2. Astrology a quartile aspect.

adj. 

3. Astrology of or pertaining to the aspect of two heavenly bodies when their longitudes differ by 90°.

• Medieval Latin quartīlis, equivalent. to Latin quart(us) fourth + -īlis -ile
• 1500–10

Collins Concise English Dictionary © HarperCollins Publishers::

quartile / ˈkwɔːtaɪl/ noun

1. one of three actual or notional values of a variable dividing its distribution into four groups with equal frequencies

adjective

1. denoting or relating to a quartile
2. denoting an aspect of two heavenly bodies when their longitudes differ by 90°

Etymology: 16th Century: from Medieval Latin quartīlis, from Latin quartus fourth