the.com/rogue wave

means An abnormally large, unpredicted ocean wave — much bigger than the surrounding sea state — that can appear suddenly out of apparently normal waters.

from 'Rogue' has long meant a lone, unpredictable deviant — think 'rogue elephant,' an animal that's broken from the herd and turned dangerous. Sailors borrowed that sense for freak waves that broke from the normal pattern of the sea. For decades scientists treated these reports as maritime folklore, since linear wave theory said such giants were near-impossible; the 1995 'Draupner wave,' recorded hitting a North Sea oil platform, was one of the first hard measurements proving rogue waves were real, not just sailors' tall tales.