wordshift tracks the rise and fall of words and phrases across 200 years of published English books. Search any word to see how its presence in print has changed since 1800, and discover the cultural, political and scientific moments behind every curve. Find out more on the About page.

Frequency data comes from the Google Books Ngram Viewer, a dataset of over 8 million digitised books in English published between 1800 and 2022. Values are smoothed using a 7-year rolling average and indexed so that each word’s historical peak equals 100, making it possible to compare words of very different absolute frequency on the same chart.

Inflection points are detected algorithmically based on topographic prominence; the same method used to rank mountain peaks by significance. Each moment is annotated with historical context generated by Claude, Anthropic’s AI system, and cached to avoid repeated API calls. Learn more about how wordshift works.

The corpus is a sample, not a complete record of the English language. It over-represents certain publishers, genres and time periods. Words that appear before they were coined usually reflect OCR scanning errors or misdated books rather than genuine usage. Treat all patterns as indicative rather than definitive.