landslide (n.) Look up landslide at Dictionary.com
also land-slide, 1841, "fall or down-slide of a mass of rock, earth, etc. from a slope or mountain," American English, from land (n.) + slide (n.). Earlier was landslip (1670s), which is preferred in Britain. Old English used eorðgebyrst in this sense; literally "earth-burst." Landslide in the political sense "lopsided electoral victory" is attested from 1888.