slightest sligh·test UK/ˈslaɪtɪst/ US/ˈslaɪtʌst/ fairly common adjective 1. (usually follows `the'') most meager “didn” Similarleast WordNet 2.1 (Princeton University). Wiktionary (CC BY-SA). CMU Pronouncing Dictionary. WordNet 2.1 Copyright Princeton University. All rights reserved.