You Pronounce It: [het-uh-roh-juh-nee-i-tee]
1. the quality or state of being heterogeneous; composition from dissimilar parts; disparateness.
Heterogeneity is a word that signifies diversity. A classroom consisting of people from lots of different backgrounds would be considered having the quality of heterogeneity. The prefix hetero- means “other or different,” while the prefix homo- means “the same.”