landslideEnglishOxford American Thesauruslandslide noun 1 floods and landslides killed several hundred people: landslip, rockfall, mudslide, earthslip, earthfall; avalanche. 2 they won the election by a landslide: decisive victory, runaway victory, overwhelming majority, grand slam, triumph, walkover, game, set, and match. ▷antonyms narrow victory; hung parliament.