Mann-Whitney test (?mæn?w?tn?) n (Statistics) a statistical test of the difference between the distributions of data collected in two experimental conditions applied to unmatched groups of subjects but comparing the distributions of the ranks of the scores. Also called: Wilcoxon Mann-Whitney test Collins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014