unprecedented
adj.never done or known before. You use this to describe something that is completely new or happens on a scale that has never been seen in the past.
adj.having no previous example or parallel in history. Often used to describe the scale, speed, or nature of a significant event that lacks a historical equivalent.
“The city is facing an unprecedented heatwave this summer.”
“The government took the unprecedented step of closing all borders to prevent the spread of the new virus.”
“The rapid integration of artificial intelligence into daily life represents an unprecedented shift in how humans interact with technology, challenging existing legal and ethical frameworks.”
Typically used to modify nouns representing events, changes, or levels of growth.
Usage unprecedented fourth
“Avi Dabush, who is running for the Knesset with Israel’s opposition Democrats party, attacked Netanyahu for mocking a critical ally at a time when Israel faces unprecedented global isolation.”
“Photograph: Jiji Press/EPA At least four people died in eastern Japan after “unprecedented” heavy rain left nearly 7,000 stranded at Tokyo’s Narita airport, and forced thousands to take refuge in government buildings.”
Common in science writing
From un- + precedent + -ed.
Etymology adapted from Wiktionary, available under CC BY-SA 4.0.