unprecedented
un-PRES-ih-den-tidadjMeaning never done or known before
Memory hook UN-PRE-CEDENTED: nothing like it BEFORE. Snow falls on the beach in July, something no one in town has ever seen before. The storm is unprecedented.
Snow on the beach in July was unprecedented in the town’s history.
In context The young runner’s win was unprecedented: in the race’s hundred-year history, no one under fifteen had ever finished in the top ten, let alone first.
Similar unheard-of, new, first-ever, record-breaking
Opposite common, familiar, routine
From un- (not) + precedented, from precedent, “an earlier example,” from Latin praecedere, “to go before.”